Does this sound like a cheater?

My boyfriend and I are 18 and we have a baby. Don't live together yet but he's over at mine most days. 1or 2 days out of the week he stays home (so he says.) His dad is always at work so when he stays home hes by himself. However, on these days his phone is always off. I'll get a few replies that's it. He says it's because his phone is broken and cutts out. Hes only got wifi at home, so when his phone is off its either because it really is broke or hes not home. He's been looking for places for us to move in together and says he wants to hurry, which makes me think he can't be cheating because he wants to hurry up and live together even though he'd be with me every day but then when there's always 1 or 2 days out if the week where he 'wants to stay home', I barely get any replies and his phone is mostly off it makes me think different. As I said he's here almost every day but on the nights he goes back home with his dad after his dad finishes work, his phone is never off and we talk all night. I asked him why is it when your home alone your phone is constantly off but when your home with your dad it barely goes off? His reply was he doesn't know and its not his fault his phone plays up. I don't know if I'm just being paranoid or I should trust my instinct. What do you ladies think?