Is it normal for baby to be VERY VERY grumpy with a cold?

I know it is probably a dumb Q- but geez, my 7 mo. old son is sooooo cranky, cries all day.... He got a flu shot and vaccinations about 5 days ago, and got a cold- don't know if it is related to the shots or if he picked it up at the clinic but he is miserable... runny stuffy nose, cough, sneezing- gave him infant tylenol, but it does not seem to make a difference. I don't know if I should bring him in or not, it just seems like a bad cold, but what signs should I beware of to know when he should be seen by a doc? sorry if it is a stupid question, he is my 1st.