Baby doesn’t want to eat

Every time we try feeding our 2 month old, he’s fussy and crying. We tried different formulas. We went up a nipple as well and we even tried hot or cold milk. We have tried everything. Doctor isn’t helping much because there’s nothing wrong with his sonogram. We tried gripe water and mycolin! Ugh any other recommendations? Did anyone else experience this? I’m losing my mind because I’m scared this will affect his growth