I think you just have a viral infection and will have to ride it out.As you are 6 weeks post chemo your immune system and blood cells should have recovered.
I dont think you will be drinking too quickly and it coming out into your stomach. Most PEGS in my experience have a small amount of serous type ooze around them that can have an odour. You would have a degree of abdominal pain and increasing abdominal distension if your Jevity was leaking into your abdomen and you would have a very high temperature. Also if you are having normal bowel motions this would also rule abdominal spill out.
Get plenty of rest. Drink plenty of fluids and continue to take Paracetamol for an elevated temperature.
Of course, should you have a persistantly and markedly elevated temp. with chills and shakes ( rigors ) and increasing abdominal pain then get to the ER.
You could also flush your PEG with a small amount of water, about 30 mls to flush the line.
Take care,
Tammy

Caregiver/advocate to Husband Kris age 59@ diagnosis
DX Dec '10 SCC BOT T4aN2bM0 HPV+ve.Cisplatin x3 35 IMRT.
PET 6/11 clear.
R) level 2-4 neck dissection 8/1/11 to remove residual node - necrotic with NED
Feb '12 Ca back.. 3/8/12 total glossectomy/laryngectomy/bilat neck dissection/partial pharyngectomy etc. clear margins. All nodes negative for disease. PEG in.
March 2017 - 5 years disease free. Woohoo!