Short period

Lexi

My periods are oddly short. Like I mean weirdly short. Sometimes I don't even know if I'm getting my period. It will be like a moment of a lot of blood in the day then it's gone. So basically it's like a three hour period. I'm so confused why this is happening to me. Is this normal ? I'm on the pill so it could affect it and I do workout but it would be nice having a longer period to know it's real