a new job

Today I started a part-time job.
I worked for the first time today, so I was useless...
I didn't know what to do and I imitated what co-workers were doing.
I need to learn what to do from them...

I was really tired because I hadn't worked for more than one month...
And I hadn't exercise...
Now I have backache because I was standing for a long time with very high heels.
It's really bad for my back!
I need to build up my abdominal mascle.

I have had backache for one and half years.
I should care of my back.

I hope I can enjoy my job and earn a lot of money!