Sleep training

Okay ladies , what are yours thoughts ? My son will not sleep longer than four hours and the only way to get him to sleep is with the bottle . So we tried to sleep train . Omg .. not good made himself throw up was shaking . So I stopped it . Bought this sleep program and is pretty much the cry it out method . I get anxious and teary eyes even thinking about having to do the cry it out again . He just screams and screams . I do the checks I try and calm him down in 30 second intervals . Doesn’t work. After and hour and 10 I resets for 15 minutes and repeat and it doesn’t work it makes it worse . Any advise ? I know so many people have had luck but we just aren’t seeing it . I’m just so tired and exhausted and emotional and I don’t want to hear that cry again . It was horrible ...