Narcissist?

How can you tell if someone is a narcissist or if they're just crazy with a bad memory?

I'll try to keep this short. I have endometriosis. I made the mistake of trusting a gyno after they recommended Lupron, which is a medication that shuts down your ovaries temporarily but has some horrible life long side effects. I was recommended it when I was a teen but decided against it. I was 25 when I trusted the doctor I went to in desperation.

My husband is now blaming me for issues with my kidneys because I, in his words, harassed doctors until I found one that would give me the shot. He claims he went with me to the appointment over an hour away and that the doctor was reluctant at first but gave in.

I know for a fact he didn't go. I asked him to go with me because it was an hour trip one way to the appointment. He wouldn't. I was still in college and remember going to my evening class after that because my college campus was midway between the office and our house. He swears up and down he was there and doesn't get why I can't admit when I'm wrong and that I need to deal with the consequences of my actions because he says I was warned about the medication. I was warned, by my pervious gyno that did my surgery to remove most of my left ovary and found endo. He recommended follow up surgeries when the pain started to get bad again, which it did, but he retired. I did so much research on the gyno I went to. I remember it being a rainy, cold day when I had to drive to my appointment.

I just don't get why he's doing this. I can't tell if he's just gaslighting me or if he really believes he was at most of my appointments. I begged him to come with me for most of my appointments and he wouldn't. But now years later, he's telling me he was there and how I was the one harassing doctors.