My period ended about ten days ago, it's three days that i'm having light bleeding and also a feel of pain, it's the first time, should i worry?

No: This can be ovulation bleeding. Watch for a few months. If it recurs then please see a gynecologist

Mid period bleeding: Are you sexually active? Was your last period normal? Check HCG. if not sexually active, there is always variation in period, alternatively may be vaginal infection and /or mittelchsmerz, pain from ovulation with associated mid cycle bleeding due to drop in estrogen.