So, I just started birth control in April and had intercourse with my boyfriend on may 1st (27th day of cycle), without protection. The next day I got my period. Since starting my birth control I have had symptoms like tender breasts, vaginal discharge, and constipation. I found that most of these are normal birth control side effects, but can I be pregnant?

While it is possible, since no birth control will be 100% effective in preventing pregnancy, odds are you aren't pregnant. It appears you had been on the birth control for about a month, which should provide the protection level expected. It was also right before your period, which is one of the least likely times to become pregnant... quite uncommon in fact.

So while it is possible, it isn't probable that you would be pregnant. Given that, you will always be waiting for that next period to show up just to be sure.