Trying To Conceive, Early Period Onset With Unusual Red Watery Flow, Severe Cramps. Cause?

on day 24 0f cycle i started bleeding ,was brown at first and then went to a thin,bright red watery flow, does not look like my usual period. have severe cramps , it comes and goes, sometimes i feel as if i cannot walk. my husband and i are trying for our second child and had unproteced sex everday this month, give or take a day or 2 that we didnt. i am worried that it might be a miscarriage or maybe im just being paranoid. could you please help me out. it is now day 27 of cycle and still bright red and cramps