is my boyfriend hiding something?

[iloveyooh]

Alright me and my boyfriend have been together for three months, in the first month he left to New York for about a month hes been back for three weeks now and the first three days him being back were fine then everything went down hill from that i came across his phone and went on his facebook i just had a feeling to i came across a message he sent a girl saying he use to like her alot then after that he wrote "surprise" he knew i went through it and he said that don't do it again because its about privacy yet he has Access to all my accounts and information so yesterday i saw he had a unread message from this girl and now his password on his phone is changed he has a thing now so when he gets a text i cant see who its from he wont let me anywhere around his phone. and NOW hes barely kisses me or even touches me we live together what does this mean could he be hiding something? Should i just leave now before i get more feelings?