Formula Questions

res932

I am going to start to supplement formula. I have some questions for those out there that formula feed. I tried DS with a bottle of formula before he went to bed last night (Similac Sensitive) he had an episode of reflux last night
(he suffers from reflux) around 1 am where he sort of gagged and then cried because he was scared. I asked the doctor and they said it was probably the reflux that caused it and the formula was a coincidence.We have also had a problem with him really acting like he is straining in order to poop or pass gas, accompanied with some fussing. After he passes it he will settle down and go back to sleep. The doctor thought it might be a milk intolerance so she had me cut out soy and milk. It doesn't seem to have done much, but now I have this fear of the formulas that contain milk. Today he had a few episode of gassiness which passed after about 10 minutes but I still wonder if it had to do with the formula from last night. Does anyone think this is the case?

I've thought about trying the formula that has the milk and soy proteins already broken down. The doctor recommended the Enfamil AR, but I have already tried thickening DS's milk with regular rice cereal and it didn't do a whole lot other than bind him up. 

I know a lot of people say that the formulas can cause gas and constipation but I don't know what is just him being a baby with an immature system, what could be formula related, or waht could just be something else. I just don't know where to even begin in trying formulas for him. I want to find him something because my milk supply seems be going down. Anyone with advice please help!