DD2 had her Hib/Men C booster on tues, and weds night I noticed she was hot-temp of 40. Rang the doc and ended up going into hospital. They couldn't find anything really to be the cause-one said it's likely to be a reaction to the booster, and another that it could be a virus. They sent us home and told us to carry on with calpol etc.
I was up all night with her and she was sick a couple more times, I have got her temp back down again (but the same happened thurs night) She is very sleepy, just lying still and staring into space.
Two questions:is it likely to be a reaction?
And how long should it go on for...Should I be taking her back in?
I'm much more anxious as my little sis is in labour with DC1 
, I really want to go and see her asap (she lives 2hrs away) She's 9cms already. I can't risk going if dd2 has a bug 
I'm sorry if this makes no sense-i'm very tired and just don't know what to do 