I had sex with my boyfriend on may 4 and again on may 19 the first time he didn't finish but the second time he cum a lot faster then usual am I pregnant?
You could be. It will all depend on some certain factors: unprotected, fertile time of cycle, when your last period was, did he ejaculate into you, etc?
Generally waiting until you missed your period is a good time to take a pregnancy test. If you do make sure you use your first pee of the day as you get the most accurate result with this.
Hope this helps