At his age Rach he will be circumcised under a GA. You will allowed (encouraged) to go in with him while he goes to sleep and this bit can be quite scary for a parent the first time. He will cry and fight against the mask and you just before he goes to sleep and then he will suddenly go limp. You leave at this stage and wont see him intubated (tube down his throat). The procedure doesn't take ever long at all and as soon as he is awake in recovery you'll be called in to hold him as he will be disorienated, confused and probably a bit scared.
The circumcisions I've assisted with (as a scrub nurse/recovery nurse) the mums have been told to pop some vaseline/betadine on his knob for a few days with salt baths. These instructions vary widely depending on the doctor who does his circumcision own preferences. They are ususally sore and uncomfortable for a day or so then it shouldn't bother him at all.
Hope his appt goes well. If you have any other questions please let me know. I'll do my best to answer them.