Air carrier Flight Attendant reported smoke detected in cabin from the pilot crew rest bunk area. The aircraft returned to the departure airport and landed with a flight attendant reporting experiencing symptoms from the smoke inhalation.

Narrative

We had reached 10;000 feet. I proceeded to the back to begin the service and start setting up when we received a call back to door 4L from the purser at 1L stating that we had to put everything away because smoke was detected in the pilot crew bunks; Smoke was coming through air vents. Carts were put away immediately; stowed securely; and we were preparing the landing in 20 minutes. There were some power that went off so we used our flashlights to do passenger checks for landing. We were prepared to evacuate. We had fire trucks in place to meet the aircraft to check for the fire. They thought this might be an electrical fire. The fire department and the police took the crew down to the crew room area in ZZZ Airport to check us all out individually and see if we needed to take any further steps to be checked. I agreed to go to the hospital because I felt that I breathed in some of the smoke from the bunks. since I was sitting at door 1L. I started feeling very congested had chest pains on my right side of my chest started getting a sore throat and dealing with a headache. So I decided to go to the hospital in the ambulance. At the hospital; they did an EKG; chest x-ray; gave me a needle to detect if I had carbon monoxide inside my body. The doctor offered me oxygen; but I felt like I should be OK. I didn't want to get lightheaded and dizzy before I went back to the hotel.