early signs of pregnancy ?

Once I got off the pill my boobs went back to their sad small size and it really sucked . This week has been bittersweet bc my boobs have doubled in size. I mean they look frkin awesome, but I'm in so much pain and they are extremely heavy and swollen. My new bras I just got over Christmas don't even fit and I was sized at vs and know for a fact they fit like a glove just a month ago. My boobs have never done this before my period so now I'm wondering if I could be a few weeks pregnant ?