hey im 18 and about 5.3. Worried about an unsual blood clot in my period. I've had a 3 week long period so far and today it got exceedingly heavy. This evening i saw this clot that looked like a fatty substance attached to the a very dark coloured blood clot. Should I worry about this? I'm pretty sure there is no chance of pregancy/ misscarriage ( although I did have sex about a week and a half ago).