Feeding Woes...

I think we have hit a wall. On Monday, Little Man has his BEST therapy session EVER. Normally when his PT comes, he prefers to "check out" by closing his eyes and participating as little as possible or he does this pathetic little cry that makes you feel like a horrible person for making him stay on his tummy. :( But on Monday it all changed- he was active & present and did stander work & reached & sat up and initaited and accepted weight bearing on his arms while sitting- something we have been trying to convince him to do for-ever. We were all on cloud nine. I felt like I got figured out- the right food, given at the right time, with the right vitamins/supplements equals a happy & energetic baby. Presto!
Then on Thurs. he started his day with a spit up. Not alot, I did'nt sweat it, spit ups happen all the time & this was small. Then he spit up his second bottle, then his third. He was able to keep a small amount of oatmeal down for lunch & I thought all was ok because he ate a big (for him) dinner. Well a few hours after that, it all came back up & he heaved for awhile after:( Poor baby:( All I could say was "Well, at least have that GI appointment in the morning!" So yeah, we added another doctor to the list because we love hanging out at Cooks.
She was a nice doctor. Agreed that he was thin (ya think?) and that for the amount of calories that he takes in he should be heavier. The good news for me was that he only lost 6 ounces with all that vomiting- he's still above 15 lbs! She signed him up for a stool analysis, sweat test, blood work & a barium cocktail so they can see how his food travels through is digestive tract. We go back Monday morning for that & we will be there all. day. long. She also gave us some Elacare to put in his bottles & I met with their dietician. We had a bit of communication difficulties as I had to remind her 2x that I was just told about 20 min. prior that we were getting Elecare because she kept asking me how I was making it. She then kept asking me what he was eating & how many calories it was- Luckily I was prepared. I have been keeping a food journal for several months & keeping track of what goes in, how many calories its & how many spit-ups he's had. Its not the first time I've had a run-in with a dietician at Cooks, I'm sure it won't be the last but they sure do make you feel like your not feeding your kid:( I then got a lecture, complete with handouts on how to obtain Elecare from the company. This stuff is gold- its like 40$ a can. Crazy! You want to know what's even crazier? Little Man hates it. He won't even make an attempt to swallow it. He makes his broccoli & spinach face and lets it dribble out. I've tried it straight up, mixed with soy milk, lessened the concentration, even mixed it with oatmeal & his DHA that is strawberry flavored. No Go. So now what?
I did get a good vibe from the GI dr. herself though. She really took the time to go over with me what & how he eats and the frequency. He has some weird eating habits- I did stress that when his feeding/food is right I can see him grow before my eyes, developmentally, cognitively, physically, its amzing, but when he gets a case of the spit-ups it sets him back ALOT. That is what has me worried. How can he be eating for so long & doing so well & then have one bad eating day & be set back weeks> He was literally half the baby he normally is during the exam.  
I am hopeful that Monday will bring some answers. I may even swing by the Nuerosurgery clinic to see if they can squeeze him in for a look. We'll already be there all day, might as well add on another dr. looking at him, right?

what's going on in there?