Braxton hicks

Ok I seriously can't ease my mind. I believe I had my first episode of Braxton hicks contractions on Thursday which would be 21 weeks for me. I don't know if it's my mind or what but I don't feel the same. I didn't have many symptoms before so it's so hard to tell if something is wrong. Over the phone the doctor said I was ok but like I said I can't ease my mind at all