We all wish that a person will not do to us what they have clearly done to others, that we are different, that they love us more and therefore wont do it.
But............. the length of time he didnt contact you on the Friday/Saturday suggests he went out that night and just didnt want to have to explain that to you.
Okay this could be because you are clingy, it could be because he is a lying cheating bastard - either way - this behaviour is suspicious after only 5 weeks and almost certainly will happen again................ he just doesnt care enough.
only you can decide if you can stay and hope YOU are wrong and he is a lovely trustworthy man or leave now and realise HE is a wrong un and will hurt you with his lies ie "no signal "
Good luck