[Product Question] How to tell if a bottle of tret is expired?

I have a bottle of .05 tret I want to use but it expires in Jan 2017. It has been exposed to heat before but it still worked after. Now that I went back and reopened the bottle the cream is no longer creamy but watery. Is it still good or should I use my .1 Adapalene until I can order a new tube of tret? All answers appreciated.