Breakthrough bleeding or chemical pregnancy?

Ok I’m kind of late posting this as this happened late April-May but I have been getting in my own head. I was taking the birth control Sprintec and missed 3 pills in a row due to me being away from home. On the 3rd day I began bleeding superrrr heavily probably going through 2 tampons within 3 hours. I passed huge blood clots probably the size of my palm multiple times a day sometimes more than one at a time. This went on everyday for about 3 weeks and then stopped once I got back on track with my birth control. I chucked it up to just being breakthrough bleeding but would breakthrough bleeding be that intense?