Is it autism or Narcissim? (Or Both)

I've been diagnosed with autism for four years. I have 'classic' symptoms, poor theory of mind, poor eye-contact, bad at reading body language and social cues. I often tend to be insensitive to other people's feelings and needs. I don't respect boundaries like time and space and I often end up taking advantage of people, from small ways, just being mildly inconsiderate to being a big energy vampire and emotional trauma dumper. Its not cute and I know that. I saw a psychiatrist who doesn't think I fit for NPD but I think that's because I'm not grandoise. I don't believe I am truly capable of empathy and I genuinely have a hard time considering others needs because I don't know how to imagine other people see things. Does anyone here have both, and can explain how one diagnosis might mask the other?