I have burning in tip of penis when urinating, what to do?

It's...: Does it occur recently or for a long time, sporadically or continually? Or just happens after frequent coitus or masturbation? Nonetheless, you can wait and see if no fever/chill, ok in peeing, and bearable yet slowly getting better slowly and surely day by day. If not resolved timely as described or still in doubt, see doc timely for more hx, physicals, and tests as needed so to deduce DX for rx.