Hey, I'm going thru the same thing right now. AF started on 19th April and lasted 12 whole days (last day last Wed)!!! Spotting on Thurs, then I had one blissful day with nothing, and it started again

it's sooooo frustrating, isn't it?!! So like you, i very much doubt I ovulated on that ONE day I had no AF!!
I went to my doctor on Friday, and she suspects I may have PCOS, so I had a blood test and should find out the results this week sometime.
I definately think you should see your doctor!
Good luck!