About 2.5months ago my kitten started eating less of his grain free food, i tought maybe he just got bored so i tried a few different ones with no success ( before he wasnt picky at all but now he refused most of the food i offered) he also got diarrhea and was lethargic, turns out he had an infection and a fever which was treated with antibiotics by my vet. His fever went away for a couple of days but he still ate only small amounts in a 24h period, barely even ate cooked chicken which he was crazy about before. Took him to the vet and he still had an infection, after another round of antibiotics he started eating but the new food( he would still refuse the old one). After a week or two he started eating less of his food again and was lethargic and very sleepy and moody but the difference now is that his third eyelid started showing when he was relaxed which wasnt the case before but his eyes where looking normal when he got excited about something or during the trip to the vet or in the vets office. Now a complete blood test was performed with FVP,FIV, FELV, corona,giardia tests which where all negative and blood sugar was normal(vet insisted to not charge me for these tests), turns out his hemoglobin and something else was lower than normal, his white blood cells where slightly elevated, platelets where very high too. Vet said he still had some kind of infection, so he treated him with different antibiotics for 5 days and then did another blood test, almost everything went back to normal except platelets which are now slightly elevated but vet said probably because he is slightly dehydrated, he also said that there is nothing physically wrong with him and because i free fed him i should try scheduled feeding, which i will try in the following days. But if nothing is phyisically wrong with my kitten, why is he still lethargic most of the time and seems depressed, has no interest in food or playing and his third eyelid showing only when relaxing. What can i do?