Feeling unwanted

I have been with my husband for about 10 years now. He is the love of my life and I can't imagine my life without him. Today I was so turned on by him and I let him know it. I decided to initiate sex and let him know how much I wanted him. He went down on me and it felt so good. I did the same but when it came time for hot passionate sex.. He got soft on me. I have never had that happen and I don't know how to respond to that. He said he was sorry and he'll make it up to me. Is he suffering from E.D? Is he losing interest in me? Does he not love me and he's just trying to make himself love me? I'm so confused and hurt and I feel so unwanted. I don't feel sexy anymore and that made me so insecure. I'm at loss for words. I will never forget this and every time we attempt to have sex I will always be afraid that he will not get aroused. By the way he's 46 and I'm 33. Please give me some advice. I'm falling apart here.🙁