Did anyone's baby experience allergic reaction to oatmeal?

My little girl has been doing great on the organic brown rice cereal (Earth's Best brand) for 3 weeks now; so we decided to add oatmeal to the daily routine in the morning and continue with rice cereal in the late afternoon...I had to get the Gerber organic brand since my supermarket did not have the Earth's Best oatmeal.  We started with the oatmeal yesterday morning and in the evening when I was giving her her bath, I noticed small red bumps (almost like a rash) starting from her chin down to her upper chest. I didn't want to overreact and assume it was due to the oatmeal so I washed her good and put some Aquaphor on her.  This morning my mom gave her the oatmeal again and by the time I got home from work, I noticed the rash hadn't gotten any better and spread a bit more over her body. Now I'm more certain that it has to be the oatmeal; nothing else has changed (regarding the lotions, soaps, detergents we use). I am washing pretty much all her blankets, bibs, burp clothes (I use dye free, perfume free detergent because I have sensitive skin) and am resanitizing her teething toys & pacis again tonight just in case.

Sorry so long... so my question is, has anyone else experienced this? Is it possible to be okay with the rice cereal but react to the oatmeal? I'm going to call the pediatrician tomorrow morning but would like to hear from any moms out there that may have gone through this.

TIA!