Uti or Pregnant?

So I have been having some really apparent pressure in my abdomen lately. I wanna say it's been over two weeks. Every time I pee, I feel like I should have more. I am prone to uti's but I haven't had any burning or itching, and the pain isn't unbearable. It's just annoying. My period is a week away, and now my breasts are getting sore. This usually happens when I get my period, but it also happened when I first got pregnant with my son.  I can't tell if I'm over reacting, or I really have something going on. I don't want to go to the ER for nothing. So, any input will help!