I had my period for 3 days had sex trying to get pregnant now bleeding again but in no pain at all can you tell me what this means??

This means you've got your period and you're not pregnant - or am I not understanding the question?

Are you bleeding heavily, like a period, or is it just spotting?

Bleeding between periods can happen for many reasons. Rough sex, tearing, infection, etc. etc.

The fact is, you had a period. Why you're bleeding between periods we can't diagnose online. If this is a concern your best bet is to see your doctor.

Good luck.