OOOHHHH, I am so frustrated with my doctor...

I am so frustrated with my doctors office right now. Ok, yesterday my son woke up with what I thought was hives, a pretty bad case. Well, I called the doctor because last time he had them this bad, they gave him a prescription for it, so I thought he might need that again. well, they said just give him Benadryl. They also said, that I should just go ahead and bring him in and get him checked out to see if it really was hives or something else, like maybe Poison Ivy.Well, it seems like every time we go to the doctor, the kids just get sick with something else, so I asked if we could give him the Benadryl and see if it went away and then if not call back and get him in. She said ok. Well, this morning it has spread and it seems to be worse in areas still itchy everywhere but less red in other areas. So, I called and asked to speak to a nurse. They took a message. Well, in the meantime, my son is really crying with his eyes hurting also and the rash is right under his eyes, so I called back and told them this to see if I can just get him in and they said they can not make appointments for rashes, they must be diagnosed over the phone first by a nurse.
Ok, well, what if it is something serious getting in his eyes?
They told me yesterday that if it wasn't better that I would have to get him in today.
When did they get to decide if my kids get to be seen or not? I mean, this is my child and don't "I" get to decide if he goes to the doctor or not?
I mean seriously, this is ridiculous. It makes me so mad.
Is there anything I can do?
This just frustrates me to no end.