Catherine,
I agree 100% with what Goldilocks said... the tighter the tops, the better... I bought a maternity bra when I was 10 weeks pregnant with Noah... and that seemed to help, I guess because there was no wire?
The best thing I can tell you is, it usually gets better... Usually around 12-16 weeks. In the mean time... perhaps you could try cooling them off with cold face washers when you can.