Cant orgasm 😞

My significant other and I have oral sex and use our hands to pleasure each other. I am able to get him to climax but I can’t seem to climax my self. It feels great what he’s doing but I feel bad when we were intimate because I felt like I was taking way to long he reassured me that it was ok he enjoyed being able to take care of me. He tells me it doesn’t matter how long it will take. I just feel bad because I cant seem to finish. I am very attracted to him he’s doing everything right but I can’t seem to finish. Is there something wrong with me? Am I not doing something right? Any advice would be much appreciated.