here we go again

So this morning at 2:30am my baby girl spit up a little bit which I wrote it off as her having to much spit from teething. At 7:13 this morning she started vomiting in her sleep so I woke her and she vomited about 6 oz of white foamy looking puke and then she passed back out after I cleaned her up and she became unresponsive to me trying to wake her so I called the hospital on my way there and soon as I got there she woke up thank god, they ran all kinds of tests found nothing wrong with her. They said she probably was just exhausted from the vomiting and the crying but said only to give water,pedialyte, and any solids she's on and no formula for 24 to 48 hours depending on if she vomits again or not. I thought we had finally figured out what had been wrong with her but I guess not. Thankfully my husband is home for season lay off now and can help so our plan is he's awake with her during the day and I'm up with her at night. She just turned 6 months and this has been going on now since she was 3 months I feel horrible