Help me, formula crisis!

So I didn't produce a milk supply and started her on formula. In the hospital it was soy and worked good, then they gave me regular bc they ran out of soy. Then once home I had some can samples of mixed variety. Used the regular enfamil bt she got a little constipated, then switched to the newborn enfamil and figured out the water/formula ratio and she became regular again. Well the last few feedings she's not eating much, an ounce at most when she has been doing 2-3 ozs. Now that I just used the last bit of that can she has diarrhea! Should I stay on this newborn formula or go on to the next sample can which is the gentle ease enfamil to see if that will help? I can't talk to her Dr til Monday so im reaching out to you expert mommas! Please help!