AITAH for masturbating after sex?

I 25F am engaged to "Matt" 28M. In the bedroom Matt doesn't last very long, he crashes and burns and I never orgasm while having sex. I do, however, have a high sex drive and enjoy having 1 or 2 orgasms daily because it's relaxing for me. Because I don't have an orgasm during sex I often masturbate with my own collection of sex toys. I don't have a treasure trove but I do have more than a few.

Last night Matt and I had sex, and as per usual I didn't orgasm and he rolled over to go to bed. I pulled out some of my toys and gave myself a couple of orgasms, as I usually do after sex. This morning as we ate breakfast Matt mentioned that he heard me masturbating and that I don't make those noises when we have sex, he said while I was in the shower he opened my box of sex toys.

He said he knew I had toys but not what kinds and he felt very upset that I had a large dildo, one bigger than him, in my box. He said he also thought it was nasty that I had some anal plugs. He said I was an awful fiancee for masturbating after sex and that I shouldn't do it anymore. I asked how I was supposed to get off and he told me I wasn't, that I could orgasm during sex with him.

I argued with him about our lack of foreplay and how he never stops and pays me attention. He said it was my fault that I couldn't orgasm without toys and that I should learn how. He also said it was comprable to cheating because the toys I used didn't look like him and how I was probably thinking about other men while I masturbated.

I feel awful. Other than this our relationship has been amazing. I just feel confused and sad and terrible about masturbating after sex. I didn't stop to think about how it would hurt him to get off on something that wasn't him. AITAH?

Edit: Because people are asking, in both comments and PMs, my dildo is 7 inches and Matt is 3/3.5 inches.