Heavy vaginal bleeding followed by brown discharge

Hi I've experienced heavy bleeding for 24 hours, more intense than most of my periods, and then it turned into a thick brown discharge. The blood wasn't similar to spotting as it was far too much, as in I ruined a pair of shorts when I woke up that morning. I'm wondering if I could be pregnant or is it a sign of something else. I've only had protected sex with my boyfriend and the last time we had sex was on the night before it started and on May 29th. My last period started on May 13th and I'm usually very regular and know that it was close to my ovulation date, but these symptoms seem too intense from everything I've read about. Does anyone have any ideas? There is also no pain whatsoever.