Risk of having to t* up blood after gastroscopy with biopsy?

i will have a gastroscopy with biopsy in a few days.

as I have very strong fear of vomiting (emetophobia) i want to ask about the risk of internal bleeding after taking a tissue sample inside my stomach, which could lead to haematemesis. (I have no known issue with coagulation, so i know i should not even think about this.. but the phobia is controlling my mind here...)

So my question really is: if there was (severe) bleeding, how soon after the procedure would the vomiting of blood occur? Or put differently, after how many hours of nothing happening can i be sure to "be safe"?

So maybe i will ask if I can remain at the hospital for that amount of time...

I know i could just ask the performing doctor, but I want some other opinions (or experiences) since he tends to downplay stuff...