Welcome, Keela and Mama!
You might want to look for a better light than the Featherbrite because that one has a CRI of 91 only and the higher, the better.
Wolf is right about the light schedule. Macaws are low hormonal birds but that doesn't mean that one should keep them at a breeding light schedule all year round and I am afraid that 12L/12D is just that. You, been a vet technician, should know very well that a healthy endocrine system is more than just opportune sexual hormone production, it regulates appetite, sleep, mood, etc all the way to the immune system so, taking into consideration that birds need the special spectral distribution that happens at dawn and dusk in order to get their internal clock in tune with the seasons, I recommend your reconsider the one you have her under right now.
Now, as to her 'unexplainable' behavior... well, actually, my dear, her behavior is perfectly normal and easy to explain: at 1.5 years old, you have a young child in your hands and young children want to be with mama all the time - that's why she climbs all over you and constantly 'feels' you with her beak. In the wild, she would still be living with her parents but would be flying around, foraging and allopreening with them as well as surrounded by her extended family, never leaving the familiar territory where she was born. In captivity, she clings to the parental figure she has: you. Captivity is very hard on parrots... The conditions we keep them under, even when we try our very best and put a lot of time, thought, money and effort into them, is not anywhere near ideal. We can't provide a flock, we can't feed them in their beaks, we can't be there 24/7/365 for them, we can't offer them the exercise they need (macaws need, at the very least, a distance of 30 ft to fly), we expose them to strange places and people, etc. So, whereas a baby in the wild would be naturally insecure and vulnerable, in captivity, this is exponentially multiplied. Besides that (and I am not trying to make you feel bad about it, I am simply stating a fact), birds from petstores are usually bred by not so good breeders which could mean gavage-fed, shipped in a dark box, not weaned correctly, high stress in a particularly sensitive development stage, etc. All pet stores tell you that their birds (dogs, cats, ferrets, rabbits, whatever) come from local and very good breeders but the truth is that good breeders don't sell to pet stores... they all have waiting lists.
So, I am afraid that my advice to you is to put up with her behavior. I know it must be a pain in the neck because even if she is still a baby emotionally, she is also a big-ass bird

I have a LSC that does the same thing and I well know it's no joke to have a big bird hanging from one's neck... sheesh! one can hardly do anything! I usually have to 'flip' him over my shoulder so I can, at least, see what I am doing because he leans forward and puts his head right in front of my face as he does this when I am working in the birdroom.
Now, there are ways you can make things more manageable. I have a very strict routine so I always do the same things in the same order. This helps him know not only that 'his' time will come but also when it starts and when it ends (I also use words like "Wait" and "Almost done" when he gets impatient as well as "OK, byebye" when he is to let me go so I can leave the room) and
posting.php?mode=reply&f=5&t=14930#each interaction also has a word or phrase so, for example, he knows that when I say "Papapa?" we will do something he loves: he perches on a special high perch that puts his head a bit higher than mine, bends a bit over, turns his head -always to the right- and putting his upper beak on my upper lip, he clicks it by opening it and closing it fast while I do the same thing and at the same rhythm with my mouth by clicking my teeth while he stares into my eyes and I hold his right paw in my left hand and caress the top with my fingers). I have no idea what this means to him or what the significance of it is but he loves it and asks for it when I take too long to do my chores

Another thing we do together is the "WEEEEEEE!" where he hangs on with his claws and beak from some kind of material (could be a towel, could be my sweater or a T-Shirt) that I swing around and up and down so he can flap his wings real fast (he can't fly at all). So I suggest you sit down and plan your days so you can have the same routine all the time and plan some 'special' activities in them that would 'mesh' with your and her schedule...Just as an example, you can uncover her cage before dawn and open it so she can come out at dawn, take out her dishes and clean it (without turning on any artificial lights until the sun is out), serve her the raw produce - turn on the lights - serve her breakfast (could be gloop, could be a chop with grains in it, etc) - do a cuddling session or give her a bath (always cold water in a warm room) so he can spend some time preening and give you a couple of hours to do some chores - do some flying or some other kind of 'tiring' activity - put her in her cage for his noon rest (this will give you time to do your stuff) - take her out and allow him to climb in his gym (I recommend natural tree branches he could also chew) - do another activity - cuddling session (mind you, the cuddling session can be nothing more than have her on you while you work on a computer, for example) - turn off the lights - put him in his cage - serve him dinner - let night fall so she can fall asleep naturally - and voila! You have a good day for both you and her!