Hi B.,
If he has a high fever, he may have a bacterial infection. In which case, you should take him in to the doctor (or even ER) right away.
The vomiting may be caused by the medication you're giving him. I recommend NOT giving him any drugs and closely monitor his temperature. Without meds, you can monitor is true symptoms.
A fever is the body's way of fighting off the illness. I am an advocate of letting the body do what it's supposed to do and not interfere by taking drugs that suppress the symptom (in this case fever). It is difficult to monitor your child's true symptoms when he's been given medication that alters them.
Along with side-effects of taking meds, another problem with giving acetaminophen or ibuprofen to children (or anyone for that matter) is that the lowered fever creates a false sense of reality. The sick person now feels "better" and does more than he/she normally would. This only prolongs the illness and sets the person up for even more complication. Obviously that is NOT the case with your son -- but the meds could indeed be making him worse.
Best to leave nature be and let his body heal itself. You can naturally help this along by what YOU eat (since you’re breast feeding). Stay away from processed foods and stick w/ lots of whole grains and vegetables. Fruits may exasperate the diarrhea; so don’t eat to much fruit until the diarrhea subsides. You should drink plenty of water and maybe even take an electrolyte replacement (like “Emergen-C”).
Best wishes to you and baby. :)
Warm Regards,
G. Van Luven