Maybe it's the rice

So we've started the baby on solids, starting with rice cereal.  Isn't that what most babies start on?  It's pretty bland and one that is least likely to cause a reaction in your child.  Or so I've heard.  Anyway, we've started that and at first, the baby loved it.  Acted as though it had been part of our routine the whole time.  I was pleasantly surprised!  We did that for about a week and then the spitting up started and the random wailing.  What happened?  I wasn't sure if it was the rice or maybe I was giving too much or the little sips of water had caused an upset stomach.  Poor baby!  So we went from two feedings down to one and for another week and now we've started into veggies.  There is less spitting up but still the occasional, random crying.  Maybe she's still sick?  She's had this little cough but not fever.  Maybe it's more a bug than the food?  Gah!  Trying to figure these things out sometimes as a parent is really hard!