My camera is acting weirdly these days... After putting fully charged batteries into it I was only able to take 2-3 shots before it turned off and showed the battery low symbol. So I took my camera to a shop and they changed the battery and cleaned the battery socket and so it was working fine at the shop. After getting home I tried to take some pictures, to test it, and it shut off again. This time, fortunately I was able to take 5 shots. Any idea what might be happening?

Camera model : Olympus FE-210.