What is the ruling on fasting on Wednesday, Thursday, and Friday, during which I made up missed prayers without performing the current prayers, and must I repeat these fasts?

Your fast is valid, but you made a grave mistake by prioritizing making up missed prayers over performing the obligatory ones. You were not required to make up those prayers based merely on doubt, and the remedy for obsessive thoughts is to ignore them and not pay attention to them. Therefore, do not repeat ablution or prayer simply due to doubts. Seek Allah's forgiveness for abandoning prayers during that period, and it is necessary to make them up.