Pregnant?

On February 14th I didn't really have sex but my boyfriend put his penis in there for literally two seconds and pulled it right back out. He obviously didn't cum. I had my period the 21st-26th but the blood was really light. Then in March & April I had a period both months from the 19th-24th and it was so light I probably could have changed my pad only 3 times. I was worried after my period in April so I took 3 pregnancy test and they all came up negative. I figured I would get my period today but it hasn't came. I'm 16 and have had my period since I was 14 but it's been pretty irregular. I haven't had many pregancy symptoms except my belly looks kind of big but it's not hard. And I have cramps. I feel like i feel something moving in my belly the past couple days. But it could all be in my head from guilt. So do you think I'm pregnant or I just feel guilty and over worrying?