Should UPT Be Repeated For Pregnancy Or Tablets Be Taken For Menstruation?

My menstrual periods are irregular may be late upto 3 months .I have shown it to Gynecologist .USG was normal .Last time i have taken progeterone tab for menstrual cycles .After that withdrawl bleeding come twice with 15 days duration. Now ,since last menstrual cycle (3rd aug) i have no menses till today i.e.13th sept.I have done UPT with morning sample it turns negative .I wish to concieve.What can i do?Whether to wait and repeat UPTtest or to take tablets for menses?