Super heavy period, could it be M/C

I have a 28 day cycle, with usually 1 day heavyish bleeding, then 2-3 days very light, I had lots of pregnancy symptoms this month (I have 3 kids already and only time I get heartburn is when I'm pregnant and with other 3 it started from about 6dpo, I felt sick when I was hungry and heartburn after I ate, very emotional and the weirdest vivid dreams) I was totally convinced I was pregnant but got period as usual after 28 days, but it was so heavy, like soaking through every 2 hours for 2 days, but only very light cramps on first day, not normal for me at all! I had to leave work I felt so sick with nausea. It then stopped for about 10 hours and came back a medium flow, this is CD 6 and I'm still bleeding and feeling sick, does anyone have any ideas what's going