An ER visit and the scariest night ever!

Okay so all 3 of us were in the ER until 8 am this morning. Pretty sure it was the most nerve racking couple hours i have ever been through. We take Pae in because she would sit up scream.. throw up everywhere and completely turn into a zombie, like non responsive limp out of it pale baby. It happened several times before I started freakin out because somethin was going on. She went from Day to NIght with hours no fever no nothing! We get to the Hospital and they rush her in and 2 nurses and a doc work on her doing Iv, blood work and a cath UA and she didn't flinch! SCARY! we had to put an o2 mask on cuz her levels kept dropping and then they gave her zofran and fluids about 30mins later she like snapped out of it! they did probably every test they could think of and NOTHING I mean everything was normal except her white cell count which means infection of some sort???? I don't get it?! All i know is is that I don't want this happening again. so all we can do is watch it and follow up with her Pediatrician. UGh scariest night of my life! But she is doing good now and we are praying it doesn't happen again!