Should I worry

Okay I’m 20 and my boyfriend 22, I just had our baby about 3 weeks ago and our relationship was going good. But know it seem like he going back to his sneaky ways. Before and during whn I was pregnant I always felt like he was cheating on me, but I never had any hard proof. I did run across some questionable txt messages Tht seem to apply a sexual relationship but it was never direct about it and some conversations look like he deleted some txts. If I even touch his phone he act like I’m stealing his wallet or something and instead telling me he bout to go somewhere he literally get in the car and whn he get down the road he’ll txt me. Idk if I’m doing to much or I have a reason for my doubts