Losing my mind!!!

If anyone’s been following my posts lately you’ll know my son hasn’t been drinking much formula, basically only night and early morning bottle and nothing during the day. He stopped drinking and eating solids completely for a day when he caught a fever from his shots. Today I guess he was so hungry he couldn’t wait and woke up at 1am and had 4oz then another 4 at 6:30am.. since then I have not been able to get him to drink but he will drink water from the bottle with no problem. Yes I’ve gotten new nipples and also had tried cold formula since he likes the cold water and nothing. Once he tastes the milk he starts crying and won’t take the bottle. My days are spent just trying to get him to drink his milk and I’m losing my mind I’m so stressed out as I know formula is so important for them. Anyone have any suggestions advice ?? Please help this exhausted and overwhelmed mama!