Bottle feeding - Formula

Im sorry I let out in this forum. I have mom guilt almost everyday cause lose my temper on my 3 month plus corrected age daughter. Before she enter infant care, her bottle feeding with formula has no issue. Every 3 hrs she surely drank 90ml at least. If not 120ml the max. This month she enter infant care as I need to go back to work to help my husband in family finance. Its been 2 weeks she has bottle feeding issue. She doesn't want to drink milk every 3 hrs. Some times 5 hrs after last fed or 8 hrs last fed then she drink. When I try to feed every 3hrs, she sucking but the milk in bottle never decrease. Few times suck then she screaming like in pain. So when to visit he PD. He do checks on her. She has no nose block, flu, cough, sore throat, teething, ulcer, thrush, fever, lung infection. He couldn't detect what wrong. Only he told me she could have no appetite due to mild viruses she gotten from infant care. Try not to force her to drink and wait for her cue if she want to drink. Afraid she will hate milk or bottle fed in future. I don't know whats wrong with her. She seems want to drink, but the milk never decrease. Few sucking, cry like in pain. Thought the teats, but PD say no need to change. My heart breaks to see her being like this. I rather she drink more milk then never. I dont know what to do mummies. Only GOD knows how I feel right now. #advicepls #1stimemom #pleasehelp #firstbaby