My monthly period was on 10 october.usyally it is 7days but on 29october i felt pain like when period and i saw yellow discharchge and thread blood ?

Post period pain: Consider blood /urine HCG if sexually acitve( or sonogram as it may be early for positive test), May be vaginal infection like mycoplasma, ureoplasma(treat wiht zithromax,or doxy), trichimonas, BV (treat with Flagyl), yeast ( diflucan). or chlamydia/GC ( Rocephin, (ceftriaxone) zithromax)which needs treatment. Also may be ovulation with associated pain/discharge. Follow with MD/urgent care.