Help? Any ideas?

Baby has on and off constipation for a few days. No diet changes, no solids yet- same formula for 3 months. Baby has passed minimum bowel movement in 3 days, just a wee bit. We are out of town on vacation, so no where close to our doc. I've given him recommended amount of pear juice. No fever, seems happy but I'm worried that he has only gone just a few "spoonfuls" if that.

Any ideas? Time to take to er for help?