Put the diabetic meds/testing device, the camera, and any other medicines you have in a separate small carrybag--if they can't fit in your purse.
Just in case you are forced to check the Weekender, you want those items to go with you. The Weekender could be lost. Do you want to spend time in Paris trying to replace those things.
One idea might be a foldable tote or backpack (like the ones made by Kiva) that are about the size of your hand when folded, but could easily carry everything mentioned above when unfolded.
It's best to check with your airline to make sure you know their carry-on rules.