Has anyone ever experienced an watery period?

Last month in December, I noticed a change in my cycle. I had two periods in one month. Which isn't normal for me. My period stayed on for 4 days. I'm on my period right now it started January 17th. On the 16th of this month I went to the bathroom & I noticed I was spotting light pink. The next time I went to the bathroom and wiped myself I wasn't spotting anymore. All last week right before my period I had unprotected sex. Me and my boyfriend is trying to concieve. My question is..have anybody experienced this before?