Fighting bottle

So my son is 11 weeks exactly. He fights every single bottle. It started around 3-4 weeks when I was breastfeeding. He would fight me every time I nursed him. He would suck for a few seconds and then throw himself back. It would go on like that for an hour. He would cry but never seemed in pain just frustrated. I went to a lactation consultant twice and the second time she told me she really didn't know why he was doing that. It just continued to get worse until 6 weeks when I started pumping and giving him a bottle. He now on formula and eats about 3-4 oz every 3 hours. It takes up to an hour to get him to finish a bottle. I've tried different bottles and feeding him in different positions. I took him to the doctor and they don't think it's reflux. The other thing is he sleeps terribly at night (not a great napper either). Sometimes he sleeps fine but most nights he wakes a lot but doesn't want a bottle. I just can't figure out what is going on. The doctor said if it doesn't get better we can try zantac to see if he has silent reflux. Has anyone else experienced anything like this?