When to test????

Hi everyone! My husband and I have been ttc for 2 years....no luck. Im 39 he is 35. My doctor is trying me on medroprogesterone to force my period because im very irregular. She also said I have low egg reserve :-( So now Monday the 17th I start my Clomid (Cycle day 3-7). Is anyone familiar with this and know which day I start taking the home ovulation pee tests? I know my doc said day 10....but day 10 from day 1 of my cycle or when i start the clomid. Thank you so much for your time! I appreciate it. Prayers, love, and baby dust to all!!