Baby can't/won't take formula?? Help please

Rachel
Hi everyone. I'm having a really hard time with my baby. I'll try to make this short but I want to include all the details so that I can hopefully get some help from y'all! My son is 7.5 months old and a few weeks ago he just refused to eat. He was BF with a few jars of purees a day. He's in 12month clothes so obviously he's a big eater. We had to start out mostly formula feeding because of a lip tie that nobody would cut and pumping didn't work for me. He always seemed miserable and I tried literally everything to make him feel better. Something kept telling me it was a belly ache that wouldn't go away for the first three months. So I worked really hard to basically relactate because I had pretty much dried up at this point and a month later he was only breastfed. What a difference that made! Immediately a whole different baby. Well he stopped a few weeks ago, maybe a month now, and my supply is completely gone. He's not having any trouble not being able to nurse since he's been on bottles before. I thought it was maybe his teething but he didn't do this with the last 4 teeth so I don't know why he would now. But that's stopped for a little bit now. It got to the point where he only had 2 wet diapers every 24 hours. He wouldn't take breast, bottle, or sippy cup no matter what we put in them and no food either. We tried basically every kind of formula the first time we formula fed and nothing helped him but it seems that it was obviously the formula right? Since it stopped when we stopped formula. i have done everything. I've gone as far as adding sugar and flavored syrups to the bottles to see if it was just the taste. I had to start making them with half goat milk and half water and then the normal amount of formula just to get him enough calories once I was able to pretty much force it in him twice a day. Today and last night he's been screaming that scream again that lets me know his belly hurts. He has no fever. No teething signs although that's never stopped his eating before. No diarrhea. A little bit of vomiting and it's been his breakfast that he had at 7am coming out all day(that's the only thing different from his usual spitting up). He has reflux that he's almost outgrown and he's been on Zantac for it every day since he was a week old so I don't think that's the issue. He's eating solids again and taking the bottles easier that last two days which happen to be the days he's miserable again. I know that I can't drink "nutrition drinks" of any kind because I have a sensitive stomach and they hurt me a lot. Most of the foods I can't eat he can't eat either. Which is the only one of my genes that he got lol -_- he has no signs of a milk allergy or lactose intolerance although formulas do make his poops and farts smell like he bathed in a sewer x10. So I'm thinking this is his way of letting me know that he isn't gonna have this formula business anymore. He's still not interested in a whole lot of foods and I'm not sure what else to do to get him everything he needs. Also if I don't get at least 650 calories in him before bed he wakes up every 2 hours to be fed. Which we have been doing his entire life until I figured out the problem and I got a good two days of sleep before his not eating thing started. So I'm also worried about the amount of sleep I won't get because I have never been a more angry person than I am these days and I really can't take it anymore. I'm physically sick several times a week because I get an 1-2 hours of sleep a night for 7 months now so please please please help me!