Real Illness or Hypochondriac?!?!

I am not sure if any of you out there have a child like mine, but I often have a hard time determining whether or not my middle child is actually sick or is being a hypochondriac.  She has always complained a lot of various things hurting her or not feeling well.  Most of the time just asking a few questions and paying a little special attention to her heals whatever is really ailing her, which I often think is middle child syndrome. 

Lately she has been complaining on and off of stomach aches.  She has complained a couple times that she has thrown up, but no one saw her, heard anything, and she was completely fine directly following her apparent vomitting episode.  But this past Sunday I finally got my proof that there is something going on. 

I picked the girls up from their dad's house, and upon arriving at home they got ready for bed.  A few minutes after bed time she came into my bedroom and complained that she had thrown up.  My husband got her settled back into bed, since I was nursing the baby.  The next morning I found some residue on the toilet seat.  She had eaten stuffed shells, so it was tinged red....which at first freaked me out until I questioned what she had eaten.  So, now I KNOW she has actually thrown up at least one time.

We have a doctor appointment this morning, and I am a little nervous.  My mother thinks it is a gall bladder issue.  I wonder if it is not something like reflux.  It seems like it is always something for her.  She has terrible allergy issues, she is a teeny tiny little thing, she has a double astigmatism, and is very near sighted, etc.  She is absolutely the sweetest, most loving, affectionate, emotional child around.  She will love anyone and everyone she meets.  I feel bad that often when she is complaining about not feeling well, "Mommy, my toe hurts, and my ear hurts, and my side hurts and my finger hurts," that I feel it is mostly attention seeking.  Her grandmother tells me her dad was the same way as a kid.

I just want my baby to be okay.  She is 8 but she will always be my baby.  So if you say prayers, can you say a little one for my sweet pea.  We would both be very appreciative.