Are you focussing on what you were assigned to do or are you running around every department helping out everybody?
Indirectly this could be affecting your happiness at work because you might say it keeps you busy and that you love doing it. I understand, but there could be so many reasons that you are not aware of which push you into being all over the show trying to do other people’s work, claiming that you are helping out.
That reminds me of a friend of mine who I had in Sea Point where we would spend months without contacting each other. My lady friend crushed at my place with her son and to be honest, my space was invaded without me noticing.
Out of nowhere I started contacting my other friend and even going to sleep over, even found myself scrubbing his kitchen and bathroom, even doing his laundry. I didn’t realize it then but after the lady friend and her son left, it came to my attention that I wasn’t happy at my place and that pushed me to becoming a servant out at my friend’s, doing work that is not meant for me. Stick to what you are hired to do and don’t give others relaxing moments simply because you are busy with what is meant for them.