my new part time job

Hi,

So a little bit about me im 18 and i am doing my a levels, i have. part time job where i work on Wed and Fri , as those days i dont have college. I work as a retail assistant in a pharmacy, I started three weeks ago, and this is my first ever job. Although i am very grateful for having a job, i just feel sad after my day is over and when im actually doing it. I was excited to start, but now i am doing the job, im beginning to feel quite down. So basically, i work in two branches and on each day, I work with a guy who is similar in age but is really passive-aggressive when speaking and is not helpful. He just came a month before me but he was a family friend of the manager who is the lead pharmacist, and he just does all the clinical stuff and the login in and basically does everything, it seems as if the manager only goes to him to give the work. He seems happy doing it and when I ask if he wants to help with anything, he's like 'No.' when the lead pharmacist does ask me to find something and i ask him where is it, as i am new, he goes it somewhere there and is just not helpful with anything. I aksed him where i could find a code for medicine as i needed to write it down, he goes it's one of the codes and i just wrote a code down (there were many codes), later on, i found him redoing what i did (probs did it wrong), like why didn't you just tell me how to do it. On top of that he never says hi, I have to always say it. Alos we never converse, they just he's just always on the computer doing something and doesn't even seem like he wanna speak to me. He does everything and seems to be the person who doesn't work well in a team. You may be asking what i am doing, well basically nothing and it's quite evident i do nothing and i feel uncomfortable not doing anything. So basically, most of the time the lead pharmacist, just asks me to sweep and hoover the place, wash the dishes and make the place look today I guess even though it's always tidy. Last Friday, I was just at the back of the shop washing the same dishes over and over again, so that I could be seen as busy and sweeping the back of the shop for the 10th time. The manager/lead pharmacist was like it's okay, you can go home now and made the other assistant stay. She's also quite intimidating. Also, that Friday she told me to come at 12:30 pm, as it was going to be a busy day for her and she doesn't like it if there are too many people walking around (guess it's me) I told them that Friday that I couldn't come on Wed as I had exams and he said ok and said i will come on fri and they hesitantly said okay yeah. Now im dreading going in on Friday, coz i feel like im just going to be doing useless tasks that have no value (e.g. cleaning a light, yes once she asked me to do that, at the back of the shop to). I know i probs sound like some kid who can't bear the fact that he has to work or something but there is no useful work for me to do, what's the point of me being there, there is no need for two assistants. Like I hate it if I'm being seen doing nothing at home, could you imagine how uncomfortable I will feel about strangers seeing me? also haven't even signed the paperwork so don't even know if I will be paid.

Sorry for the long rant, needed to get it off my chest.

how did you get that job. pls help!!