Proof based math for physics student

Hello. I find myself struggling in my first proof based math class, number theory. I have taken math up to linear algebra and differential equations. It is elementary number theory so it really should not be that hard. It was probably the easiest class available that was proof based. However, the questions are all either too easy or too hard. Some questions I can immediately see the answer upon reading the question. Some questions, I go through all the definitions, theorems, all the proof techniques I know but I could still not prove it. When I later find the answer, I realise that I needed to use a clever trick or some identity that I would have never thought of using. Of course, the class doesn't teach those tricks or identities since they would be strategies specific to a problem i.e. unable to be generalised. Is math really just for those who already get it? It seems that you just have to be creative and know all those tricks to be good at proofs. Does it get easier? I originally planned to double major in math and physics, but I don't think I enjoy this part of math. Is proof based math even useful for a physics student? Of course number theory is not going to be useful but what about real analysis and abstract algebra and topology?