Pain, hunger, stress, none of these are emotions. These are all symptoms of how information is received and read by the fish's body.
Happy, sad, mad, these are emotions cause by hormones, endorphines etc in the body and read by different receivers.
Basically it sounds as though you're asking if we can relate fish to human emotions, no.
Fish see us as the food bringer. They are hungry. They go nuts for food. That is all.
Dogs see us as part us the pack. Dogs have emotions. Dogs see us after we leave for five minutes and act like we've been gone all day. They are pack animals. They need love, companionship.