If my baby got sick after her first rotavirus vaccination, should I tell the doctor not to give her the next one?

Yes. I would still recommend receiving the rest of the series however. Remember that rotavirus is the number 1 reason for hospitalization for children in this country.
No. You should discuss with your doctor the symptoms and decide if it is worthless to go ahead with a second immunization.
No. It depends on what you mean by "got sick". A typical reaction to the rotavirus vaccine is diarrhea or loose stools and possibly a low grade fever. If this was the reaction, it is generally safe to receive another vaccine. Discuss with your doctor the best option for giving the next set of vaccines.
Yes. If a baby gets sick after a rotavirus vaccine, the parent and doctor should discuss the events to find out if the sickness had anything to do with the vaccine, or if the sickness just happened to occur after the vaccination by coincidence. Only then can they decide whether or not to give the next rotavirus vaccine dose.