(Sorry for the long post but didn't want to end up dripfeeding)
My 2yo DD has been suffering with a mystery condition for 2 months now. It started with one tiny sore spot on her head, with a crust on it, and swollen lymph nodes. It didn't get better and she developed a couple more crusts, so we took her to our GP; unfortunately he was on holiday and we got an intern, who gave us an antiseptic and said it was 'Nothing to worry about.'
I was concerned by her dismissal of it, and after over a week of treating it as prescribed and it only getting worse, we went back, and got our GP this time. He wasn't completely sure what it was (according to my husband who has handled all the appointments- we have an EBF 2 month old and we're always in the waiting room for an hour or more so agreed it makes sense for him to take DD), but prescribed an antibiotic (Amoxicillin) and more antiseptic.
DD did NOT like the antibiotic, but using a variety of tricks and methods we got through the 6 day course, but her condition did not improve. She has also had diarrhea from day 1 from the antiobiotic.
Went back to the GP again, he said he thought it was a staph infection; prescribed another course of the same antibiotic, more antiseptic and a special skin treatment to do on her scalp each day.
DD was pretty well fed up of the antibiotic, and I really did not like the thought of giving 2 courses to such a young child, but DH said GP knows what he's talking about, and we just had to do it. So again, every trick in the book was employed, we overcame plenty of tears and got through the 6 days again. Again, no improvement.
Took her back to the GP, and he then said it is impetigo, prescribed the EXACT same thing as on the second visit- so now we're 2 days into a THIRD course of the same antibiotic, and I can't see any change for now. DD is now getting so upset by having to take the medicine that she is starting to scream and cry as soon as mealtime approaches (and she has always been a wonderful eater). She is consistently gagging and spitting out at least a part of the dose since we started this third course- and I can't blame her, she hated it from day 1 and has now been on it for almost 3 weeks 
I'm out of tricks, out of motivation as I don't see why it would work now after 2 failures, and so stressed at how it's affecting DD (not only making her hate mealtimes, but I dread to think what it has done to her digestive system). I don't even see the point in continuing with it now, and I don't want to take her back to the GP again, as I've now lost all trust in him as a doctor. Seriously, 3 rounds of antibiotics for a 2 year old, without running a single test or anything to even confirm what it's supposed to be treating? He's been our GP for over 10 years and I've always had a very good opinion of him, but this has ruined that.
DH has a high opinion of our GP and while he's not really thrilled, he thinks we should just do what he says. It already ended up in a big argument when he got back from the last appointment and I was so unhappy with the prescription.
I'm going to ask DH if we can at least take DD to a naturopath or homeopath, to at least get a second opinion and something other than more antibiotics!
I'm at my wits end and so disappointed with our GP!
YABU- I would stick with the GP
YANBU- I would be looking for another opinion