I wonder what it could be..

So I had a doctors appointment last week because my periods are just really strange. Before I actually start my period I have what looks like old blood for 4 days and then I start to get heavier, this lasts about another 3-4 days.. they're irregular, spotting, very sensitive when having sex! Period pains when I'm not on my period, through out the month. I got told I could have Pcos and that I had to have a blood test. Got my test results back today and all normal. 🤔 it's leaving me puzzled.