UC major help? (specifically UCSD, political science vs communications)

I’m a current applicant, hoping to get into UCSD and entering it as an undergraduate freshman in the fall of 2017. On my application, I applied as a political science major, but now I’m having doubts. I think I find more interest and have better skills to be a Communications major.

Is it easy to change my major into Comms? And if so, how would I do that?

Still, as an inexperienced and indecisive teenager, I’m not too keen on ditching political science, so I’m considering double majoring in Poli Sci and Comms. Is that difficult or costly to do so? Or would having a major in one and a minor in the other be better? If it helps, my first two choices for colleges are ERC and Marshall.

I apologize for my many questions, but I am grateful for any responses. Hopefully I get into UCSD, but if not, I’d still have the same questions for any other UC that accepts me.

I suggest you post your questions in the UCSD forum: http://talk.collegeconfidential.com/university-california-san-diego/