Blood Clots tmi* no pics *

what is normal when it comes to blood clots. I know blood clots can be normal on heavy days, but how many is normal I'm passing like 6 to 8 clots on my heaviest day. some are smaller while most are the size of a nickel or quarter. I have had larger ones but they arnt frequent. They will cause me to bleed through a super plus tampon in 2hrs. I have mentioned it to my doctor...but then I ended up pregnant and miscarrying so we never really looked into possible causes as I wasnt expecting another period for a while. I had a pelvic ultrasound shortly before the miscarriage and they said nothing looked abnormal, so I'm assuming everything is okay but my periods are getting longer, cycles less predictable, I ovulate early, and my periods are getting heavier with more clots so I dont know what to think?? I'll be back to see my doc if I'm not pregnant this cycle.