Is Severe Abdominal Pain And Back Pain Symptoms Of A Miscarriage?

im quite confused and dont know wot to thing..i normally get my periods between 12-15 of ev month but this month i got it yesterday and the pains are very severe...i cudn even walk this morning my back was hurting alot and my lower abdomen too......even after taking pain killers the pain was still there.....i dont know wot to think,also like abt 2-3 days ago when i was with my partner together i kinda had bit of blood spoting during sex,but then i ignored it thinking maybe because its my time,but now i dont what to think......is miscarriage a possibilty altho i didn have any symptoms of pregnacy?