Periods & Sex.. At the same time..

I'm supposed to be getting off my period in about 2 days. So my flow was very light and I could tell that I'm close to getting off. Well, with that being said, my boyfriend & I decided to have sex, twice. Now my period has become a medium heavy. So my question is, if you have sex on your period, when you're nearing the end of it, does the period suddenly get heavier?