Watching porn

So I've been on and off with my boyfriend for about 5 years now and I recently told him that I'm bisexual ( but he has known for awhile). He really wants me to experiment but obviously doesn't want me to cheat so he encourages me to watch lesbian porn while I'm alone. While today while he was eating me out he put it on for me and I loved it but I found it weird with him right there! Does anyone relate to this? Will I get over it or should I just not let it happen again?