is there a possibility I'm pregnant or am I just freaking out?

I am on the pill and usually take it at the same time every day and I am pretty good at taking it but about a couple of months ago I did have unprotected sex and a month ago the condom burst with a different guy. And now I'm getting larger around the waist and my boobs have grown a little and they are a little firmer than normal too and I'm starting to freak out. I never have my period and I'm probably to have mine (I skip periods and only have them every 3 months) Thoughts???????