It's a neat idea, but it needs some changes in execution. I think turning into a can at-will would be hilarious, and maybe even useful sometimes!

Potion Affinity is far too good. At even mid-levels, it means extremely cheap healing with no surge cost, and similarly easy access to other useful effects. I would suggest limiting uses of that ability, perhaps to once per day per tier. It's still very worthwhile, but not outright broken.

Life Drop, on the other hand, doesn't seem very good. You won't be healing many HP for the cost of a surge. I would consider increasing HP healed to half-level + 3 per tier + con mod, and the creature who consumes it can make a saving throw. I might also specify that you are creating an item (probably Tiny), and that it costs a minor action to consume it or give it to another creature. If you do that, then it's fair to let the Werecan consume the Life Drop with the same action that creates it.

That seems balanced overall to me, but it's possible I've made an oversight.