Phone - Dying Battery?

[layziie]

Yesterday I phone started to turn off every few seconds after I installed 250mbs of music onto it. The battery bar was full but the phone only lasts for max 10 seconds.

Does this mean the battery is dying?

(extra)
phone model: 7373 nokia
SD card: 512mb (mini)

 

[WorldIndustries]

Does it do it only with the SD card inserted? Might be a bad card.