Help i think my bubba have impetigo?

i have a 3 month old boy and his sister had impetigo like last week and is still on antibiotics for it. now i think he has it as the doc told me it starts of as pimply looking things and then they break and it becomes crusty yellow goow on a scab anyway he had the smallest scratch on his lip and it has gone a little like the yellow stuff and im freaking out! my partner says im just being paranoid and that it is just a normal scratch but i dont think so as he has about 5 pimply looking things on him which i think look diffrent from his usual rash that is all over his body partner thinks its the same tho but he laid back and im always paranoid about things! anyway what i wanna know is has anyones baby had this before? and how young? and also is impetigo really that serious for bubbas? and could it wait till monday to take him to docs?