Oh, how sad for you
That must be crushing you....I am sure your baby will get over it when he gets better. If you are the one giving the meds, he is probably associating you with the discomfort....my little Tango is around 4 months old and he sees what my 8 year old Pico is going thru and I think he blames me....yesterday, he acted afraid of me and bit me. I ignored it and picked him up and kissed and cuddled him like normal. Right now Pico is asleep on my chest and Tango is sitting on my hand watching the screen on my laptop while I rub this back with my thumb.
I would just act like you always did with him and not let him pick up on your feelings of being upset. Build back his trust by being steady and secure with your love, best of luck!!!