The most logical explaination from this brief incomplete history points towards self trauma induced ottitis externa.
Please tell whether you have pain in /behind the ear ?
Any change in hearing status?
Any discharge coming out of ear,if yes foul smelling or non foul smelling?
Next Steps
You need antibiotic ear drops with steroidal components.
Take pain killer of pain associated as per the pain levels.
Health Tips
No more set ear trauma by finger tips or ear buds
No water should go in while taking bath.
Use cotton with vaseline in ear while bathing for a week