I took metamucil for constipation..now it's loose kind of like diarrhea..should i take imodium (loperamide) ad or diarrhea meds or just wait it out?

None of the above.: If the "diarrhea" is not fulminant--i.e., mostly water accompanied by cramping, don't worry about it. The colon is designed as a "low pressure" environment. The less force needed the better. Metamucil is a "bowel normalizer"--it helps both constipation and diarrhea. Consequently, you can take more metamucil if you want to "firm up" your stools a bit. Having loose stools is not a disease.