Could I be pregnant????

Okay well I am really freaked out my boyfriend and I went on a trip to California we left Friday came back Monday we were over there for about 4 days and well we had sex over there 3 times in the shower and no condom but he didn't nut in me he came outside n also once we got back we had sex in his room but with condom but now it's Thursday and I started with pain and I have been lightly bleeding and getting cramps also I keep going to the restroom to pee, and I keep getting lower back pains, I am really scared and worried I haven't taken a pregnancy test yet. Should I worry???? 😰😰😰