I feel like i've damaged my ankle more than what the doctor gave me for a prelim-dx. currently getting treated for a sprain. if i relax my foot it feel like my foot just flops and nearly separates itself from the ankle. should i ask for another look?

If you can move your foot and the movement is somewhat limited due to pain, you are fine, no need to seek for a second opinion.

I think it's a good plan to have a follow-up exam. If your ankle didn't swell and turn black& blue, it would be a good sign that no major damage to tendons or ligaments occurred or a micro fracture occurred. I assume you're still applying an ACE bandage appropriately.