I need both of your ages, because it is somewhat relevant.
However, my first thought is he is very self-conscious about his erectile dysfunction. Try to make it a positive, talk to him and say how much you like to be with him. Try to do something different, buy some new lingerie, ask what his fantasies are and pick one you can do for him. Also, lack of exercise decreases libido. I'm 40. When I don't exercise, I lose libido even though my testosterone is normal. My doctor says there are other chemicals involved with libido, it's not just testosterone. So, he needs to exercise 40 minutes per day, 3-4 days per week. This will increase his libido. Even doing a stationary bike 40 minutes each time will help. When I do my bike I read or watch TV.
As for oral sex, you may be brushing your teeth on him, which is very painful for a guy, and he may not feel comfortable telling you about it. You can try Gummerz, which is a thin tooth covering designed for oral sex. Only $7, and they work, and you don't have to focus on your teeth anymore. You can focus on technique. Google it. Gummerz.com.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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