Which of these are possible?
  • The battery of my phone gets drained very quickly./drains very quickly./dies very quickly.
  • These white pants get dirty fast/These pants dirty very fast.
  • I'm sick of being here already./I'm already sick of being here.
Thank you
1. all are fine (but I think I'd simply say 'my phone's battery')

2. get dirty

3. already sick
For the battery it is better to use "run down" not drain. "Drain" is related to such as pipe, sewer etc.

"These white pants get dirty fast." and "I'm already sick of being here." are better than the others.