I had missed my periods.LMP was 18th feb.I had intercourse on 3rd and 4th march.UPT was negative on 22nd march.we used withdrawl method.my periods are regular

Wait until your period is at least 2 weeks late, then test using first morning urine. If that test is negative wait and see what happens with your next period. If you miss it, test again or get a blood test.

The withdrawl method is not a form of birth control, it means you're having unprotected sex, which means you're trying to conceive.

Good luck.

Thank you so much.but today I again did UPT and it is invalid.I m worried

Are you testing using first morning urine?

No.I used afternoon urine