When does it get better???

My little girl has been on prevacaid for 5 days now and we are continuing with the Zantac…but she is screaming more. The doctor said the prevacaid should work right away but I’ve read on here it can take up to two weeks. The ped doc also didnt think we needed to see a GI but we are going to anyway.What will the GI do at the first appointment?? We are going crazy the last 4 months have been brutal…my poor little angel Please someone out there tell me that the prevacaid will be work soon