How soon can you do pregnancy test?

[SallySummerPop]

If the unprotected sex was on Saturday 15th, but period was due Tuesday 18th and hasn't come, how soon can I do a pregnancy test? I don't know if my cycle is regular cos I have changed contraception recently

Usually about 14 days after unprotected sex. But if you're saying you had sex 3 days before your period was due, I highly doubt you're pregnant. I'd say it's highly likely changing contraception is messing around your cycle a little bit.

You could have done it on the 18th. However if you only had unprotected sex 3 days beforehand, it's unlikely you're pregnant.

Thank you! It would be such bad timing for us. I knew I'm my mind that it's unlikely but hearing someone else confirm helps.

You're highly unlikely to have a 3 day luteal phase. It's unlikely in a 28day cycle for example to ovulate cycle day 25.

Periods can be late for other reasons. If for some reason your periods are irregular you can test 2 weeks after unprotected intercourse.