How long after my period ends can I check with a doctor to see if my UTI is gone?

The next day. U can go in and give them a urine sample if necessary u can go on your period if u clean your self off well before u do the sample, or they can do an in and out cath if necessary, if u still have sxs u need to get that check asap.
Base on symptoms. No "redipping" or culturing is required- if you have no symptoms of a uti, then your UTI is "gone"; if after one day, you continue to have symptoms , then you still have a UTI or else, something close to it- your doctor should be informed and a re-evaluation done.