AA, facing a flop donk allin.

I would never donk shove. When villain does this I think he might be a fish.
I think you could fold and wait for a better spot to take his money. You have invested only 4bb and now you have to risk your whole stack.
On the other hand I do not hate calling there because we are short stacked and villain might do that with something stupid like AJ or KK.

Edit:
I calculated this. You would need 46% equity to call this profitably. So villain has to do this with sets, AA, 3 combos of KK, 2 combos of QQ and 4 combos of AJ. Given that you are short and villain might be a fish I think that is close but maybe folding is still the best move here.

I recommend posting a full hand history of the hand next time. Then it’s easier to give feedback on this hand. If you don’t know how you can always check the https://forums.pokerstrategy.com/forum/thread.php?postid=1432571#post1432571 thread.

Cheers,
SDK1987

We can discount the top pairs as he can 3b with them preflop.
Still for this stack size you can call sometimes.

I think we can call with those stacks. Villain is most likelly a fish which make me thinking that we might have enough equity vs his range. On the other hand, we could take a safer path and fold (but watch him closelly if those weren't speed tables or something).

Given you had 50bb there's no discussion whether you should fold.