Miscarriage or very strange period?

So these last couple months I had a really strange series of what I thought were periods but I’m not sure anymore. Last month what I thought was my period was a tiny bit of brown spotting 10 days later than my usual period. I usually have 7 day periods on a pretty regular schedule but I only spotted for about 3 days. Then this month my period came 11 days early, extremely heavy from the onset which isn’t normal for me, bright red blood and a lot of chunks, and waaaay worse cramps than normal. I’ve currently been bleeding red for about 10 days now though the pain stopped on day 4. I have an iud and my periods are pretty regular as I said, so this is a bit strange. Is it possible that I got pregnant and had a very quick miscarriage? I’m doing okay right now, not in pain and no other concerning symptoms. It’s quite possible that my body just decided to skip a period and is over-compensating.

Before anyone says anything I am planning to go to the doctor but I haven’t been able to yet. Also, I never took a pregnancy test so I don’t know if we’ll ever know for sure.