My 88 year old father had both of his Moderna vaccine. First shot, he only was really tired for about three days. Second shot... oh boy! I feel so bad for him. Five days after he was just tired. I expected that. Day six... he paged me in around 4am because he was throwing up (which was only a one time incident). His nose is so drippy, and coughing a lot. Nine days later, he is still so weak, and the only thing I can get down him is protein shakes. I really believe that this is some side effects from the booster. However, I just wanted to see if any other caregivers had bad side effects with their LO's, and if so, how long did it last?
Despite all the hullabaloo about the greatness of these still relatively untested vaccines, they're not really tried and true beyond the limited testing in a rush to get vaccines to market, and the medical community is still learning about them.
I hope you can get immediate help for your father.
I would google and see about expected side effects, but given it is this many days something else may be going on and could be anything, even allergies with that runny nose.