Late 3 day period and bleeding heavily

Last month I was late 17 days and I bled for 3 days and it was pretty much light. This month I was late 3 days and I'm bleeding heavily. To the point after 30m my pad is soaked with blood and I bleed through. I never bled this hard before. I thought I was pregnant because I had symptoms but then all of a sudden I started my period and I been bleeding heavy since.