How to fix my DS3 if possible?

[MikeCL]

I've only noticed it in BF3 but say sprinting where you press down on L3 It will cause me to throw a health pack while running, or it will switch to the pistol and shoot a few shots off.. It seems after awhile it's not so bad but it ends up giving away my position.. I don't understand how pressing L3 is enough to trigger the D pad up button for say a health pack or ammo.. It's really annoying and if the PS4 was not coming out I would have picked up another controller.