U understand doesn't mean u have to get. Your instructor probably poisoned u so deeply without explaining needs analysis. D7200 is still a very competent camera and hold many advantages over full frame. Look at my gears, i have so many, and can easily afford full frame but i didnt.
Actually what do u shoot to warrant a full frame? Many beginners keep upgrading for the sake of doing so, without looking into their real needs. Rest for a few months n u will realise it is not necessary for u to get one. Go out shoot more to outgrow your existing one first. Having a better or more expensive camera doesn't guarantee it will translate into better pictures.
If u r really insistent and have the budget, then go ahead. U will face more dilemma with lenses later on. Good luck gear head.
Go finish your course first, than shoot with your existing gears for a year or two, collect 20 pieces of your best work from various topics you have shot. Look at them, you will know what you really need by than.