This depends, we have to apply logic, like the Vulcans do.

If it's the nasty in your pasty then you're not a virgin and negates the whole situation. Therefore, by proof of contradiction, the "past" you is actually another separate entity from another timeline, and you've achieved sex.

If it's a future you then it doesn't count, as you can't prove it wasn't merely temporal masterbation.

Even the Vulcan science directorate cannot refuse this.