He's been really stressed, so even if he is better, he'll take a bit to calm down (both of you).
Rather than wait to see if he does poop blood, call where ever it would be that you would take him if he did and talk with them. Ask if does, you assume to bring him in right away, etc. Just talk to whoever is there so you have touched base with them. It'll help you feel better and you will have a plan if something does happen. Being prepared is a good thing
Sending prayers!