General

CO Questions from a noob WK

I'm just wondering what happens in each of these situations:

1. I cast lvl 18 fire charge, then use CO. Does my damage increase?
2. I cast CO, then cast lvl 18 fire charge. The CO timer expires. Does my damage decrease?
3. I cast HP recovery, then use CO. Does the time i need to wait to use HP recov again decrease?
4. I cast CO, then cast HP recov. The CO timer expires. Does the time i need to wait increase?

Thanks for your help.