Bras, boobs,babies.

Ok, so I started out a small A. Within a months time I needed new bras, so I got a nice soft B sized bra. I normally wear a push up (VS cotton were my favorite! ) that was soooo uncomfortable when I was sore. I got Warners soft cups with no underwire. I spent a lot, more then I do at VS (if you can belive). Now I feel like they are tight and I need more room. Should I wait or get another size? I'm 17 weeks. I can't belive my boobs are still growing but every day they feel bigger. HELP!