Normal to get angry at your boyfriend when he goes up town with girls?

My boyfriend told me he was seeing his single friend for a catch up with a night in at his with beers etc. But then he came into my workplace and told me he was going up town. His friend had just been in with 2 girls and he mentioned that they were going up town. I asked my boyfriend if he was going with his mate and those 2 girls and he said yes. So he didnt tell me until 5 minutes before he was going that he was going with girls which obviously means he will be with them and dancing with them all night. I also asked him to text me.. just once so i know what time hes coming over tomorrow and he hasnt bothered. It just seemed dodgy that i had to figure it out and he hadnt told me and im even more angry that he hasnt text. There have been occasions he goes up town or for drinks or to parties and there are girls there that hes 'happened to bump into' Hes had pictures with them and some were of him dancing with some girls in a group and some of him with this girl cuddling up to him in the smoking area of the club. Im kind of getting sick of it. I dont mind him going up town and having a good night with his mates but i dont like it when hes surrounded by girls even if i know they are friends. Is it normal to be angry about this?