Hi H.:
I am a mom of 1 boucing 8 month old son. You mentioned that the baby has a bad diaper rash and that you were on antibiotics over the last couple of weeks. I was given antibiotics right after my delivery as well and a few weeks in to nursing I noticed my son was getting a little red bottom, after closer inspection of his tounge and lifting up his upper lip, I noticed that he had thrush. He got it from the antibiotics that was in my system, which in turn killed off the very few good bacteria in his little immune system, I did have to supplement with formula because of this and by the time both of us were cleared of the thrush (because the baby inevitably passes the thrush to your breast)and you both must be treated seperately fot it.... my milk had dried up :( and to this day, 8 months later we are still fighting this thrush every 3-4 weeks. I just wish the doctors would have told me that this was one of the complications from breast feeding a newborn while I was on antibiotics...
So, just to pass this info on to another new mom, check your son's mouth/tounge/throat for any white patches that can not be easily washed away and looks thicker than milk.....The diaper rash/loose stool is a sign of thrush because babies that ususally have it, the fungus works it's way through their whole system.
As for the non-stop nursing, that is normal for breast feeding babies, for some of that time you might even notice that he is not even eating, until you try to take the breast out of his mouth and then he will began to suck again, mostly he is just probably very comfortable and doesn't want to move out of that position, it's the closest he can be to you other than being in the womb and that is what he is familiar with; also about 1 month, 3 months and a couple of other times in the next few months they go through growth spurts and they need to eat and sleep a lot more to supplement all the work their little bodies are doing.
hope some of this helps...I know it's exhausting, but that's why we were chosen to be the mommies because our men, as much as we love them would have handed in the towel a long time ago (smile)