Hefalump, i accept that you feel stupid, but I don't think you are stupid. We beat ourselves up a lot (been there done that, still do) over things that are simply...human?
I know it sounds trite, but what would you tell someone you deeply loved if they said that about themselves? I think you'd probably cut them some slack, be supportive, compassionate, encouraging.
Could you give yourself just a tiny bit of the same kindness?
If not, could you accept just a tiny bit of kindness from us when we tell you you're not stupid? I hope so.
Sending you a virtual hug