Idk what to do... Please give me your opinions

So my bf and i go out to breakfast about 3 times a week. We've havent been together for soo long but we are in love, he is my soulmate and we plan to get married in a fee years. Well this morning he was showing me a video he took and after watching it I decided to look at his pics because I wanted a selfie of him lol
Well i came across some pictures of other women and got a bit mad. He asked and even thoughtli didnt want to ruin breakfast he insisted so i told him to unlovk his phone and showed him the pics... He got really embarrased and proceeded to explain that he uses these when pleasuring himself. I know hes telling the truth but this still bothers me... I dont want him looking at other women like that... 
I mean he did say that it was just an old habbit and he deleted the pictures... And later he apologized. Btw we recently started having sex. I lost my virginity to him a few weeks ago...so i understand that he useto do this but i dont like the fact that hes doing it now...What do you guys think? Should I be mad or concerned?