Oh my
I am so sorry that you have a very poorly guinea pig and that your parents are refusing to help you and your boy. This is an awful position for you to be in.
I must ask this question and am trying not to sound awful as I do not know them but when they allowed you to have the guinea pigs, THEY were taking on a responsibility and it is very wrong of THEM to deny your boy of veterinary treatment. THEY have an appalling attitude
The responsibility ultimately lays with your parents and not with you which is why I have capitalised 'They' as none of this is your fault.
Can you please inform them of the 5 freedoms which every animal owner should bare in mind when taking on an animal. These are the 5 freedoms and in denying your boy veterinary treatment, they are breaking these freedoms:
FREEDOM FROM HUNGAR AND THIRST- By providing enough fresh water and the right type and amount of food to keep them fit.
FREEDOM FROM DISCOMFORT - By making sure that animals have the right type of environment including shelter and somewhere to rest.
FREEDOM FROM PAIN, INJURY AND DISEASE - By preventing them from getting ill or injured and by making sure animals are diagnosed and treated rapidly if they do.
FREEDOM TO BEHAVE NORMALLY - By making sure animals have enough space, proper facilities and the company of other animals of their own kind.
FREEDOM FROM FEAR AND DISTRESS - By making sure their conditions and treatment avoid mental suffering.
The RSPCA believes that anyone responsible for looking after animals should try to give them the 5 freedoms.
Guinea pigs hide illnesses very well and the fact that you can tell he is poorly means that he is very poorly. Here are the symptoms for a uri
http://www.guinealynx.info/uri.html please read the link and show it to your parents if necessary. To have any chance of survival, your boy needs to see a vet and have a course of antibiotics at the very least.
I feel so sorry for you and your parents really need to take responsibility and act quickly.
I am conscious of your age but where about's are you located i.e. are the in the UK or elsewhere worldwide? Providing your location will allow us to advise you further on what to do next.
Can a mod please move this thread in to the Health and Illness section where the OP may get more replies and offers of help.