Possible Immune Response to Low Dosage of Remicade?

So I was diagnosed with Crohn’s in 2011 and I’ve been on Remicade since then as well. I recently switched doctors because my previous one retired, and at my first infusion with my new doctor I only received 390mg when I am supposed to be getting 800mg… (long story short, it has been a CIRCUS trying to figure out how/why this mistake was made, but here we are🤦🏻‍♀️). I got this last infusion on July 12, and since July 31 I have been in the bed with low grade fever, bad body aches and headaches, and extreme fatigue. I have also tested negative for Covid. Could this be an immune response due to the lack of medicine in my system? I would ask my doctor but it’s near impossible to get in touch with him🥲(hence why all this has been a nightmare).