Could Severe Cramps And Back Pain Along With Heavy Bleeding Indicate Miscarriage?

i think that i may be having a miscarriage but im am not sure. i started bleeding on monday but before that i had no cramps or anything like that. now i have been bleeding for 3 days kinda heavy. more heavy than my period with strong cramps and lower back pain. the blood is bright red and has clots. the cramps and back pain are worse at night