The Navy and Hat Size?

This may sound ridiculous but I'm planning on joining the Navy (currently doing very intense personal fitness training to get ready) but my only concern came up randomly in my mind the other day. I wear a very large hat size, like I can't wear just any normal sized "fits all" cap. I wear like a XXL or maybe even an XXXL, big head. Can you still join the navy with a big hat size? I know this sounds completely dumb but I'm just hoping this stupid thing won't stop me.

If I gain muscle mass, will my clothes get smaller?

I have been doing personal fitness training with my instructor since April and I feel like I am not really losing anything. My weight has stayed the same, but my muscles have gotten larger. Now half my jeans don't fit me anymore. How did this happen?

Voting Question: What are some good colleges and careers to fit me?

I'm a junior in high school and I need to start thinking about career choices and what to go to college for. I have a few things in mind like drafting and personal fitness training because I love to work out and help others but my mom says I can draw very good and should consider drafting. So here is some information about myself. Like I said, I love to work out, play sports and be around sports. I can draw pretty good and I'm pretty creative. My strong subjects in school are Math(Algebra & Geometry) and Biology. My weak subjects are Social Studies and Chemistry, English is average. I need some career and college suggestions to take into consideration. I live in Kentucky. I haven't taken the actual ACT yet but I took a predictment test and it predicted my range from 22-26. I would like to make really good money with whatever I do(as I'm sure anyone would, haha.) So please leave any college, majors/minors you think I would be good at and it will be greatly appreciated. Thanks!