Autism or narcissism mother

Hello, does anyone struggle to understand their mother's behaviour and wonder if she is autistic, or narcissistic? I have ptsd from my mother's screaming and yelling fits in childhood. The thing is, recently I went to a therapist who suggested she is narcissistic, covert type. However I have aspergers and I really wonder how a mother with Aspergers might appear if she had ptsd herself and no autisn diagnosis due to masking her whole life and being born in the 1940s. How could you tell the difference between the notoriously difficult to spot covert narcissist mother, and a mother with Aspergers and ptsd and possible depression? Mood swings, difficulties with empathy, meltdowns, yelling, blame shifting, really hurtful lnsensitive comments, raging if criticised or perceived to be being criticised, different masks or persons, etc etc how would one ever know? I'm looking for anyone with experience in their own lives with this please, I'm interested to hear about your narcissistic OR autistic mom. Thanks a lot.