Started a new retail job and was fine at first except I could quickly see that most people here are very depressed (Small store - only about 10 people working here with different shifts), barely anyone would say hellos in the morning etc.. Recently though shit has just been piling up and somewhat annoying me.

Theres this one female coworker (Same role) who I'm pretty sure is shit testing me and trying to annoy me but at the same time embarrassing me, anytime she is serving customers she say will "Leaninuk JUMP ON THE TILL" with the tone of voice that shes demanding me to and making me seem like I'm some shit worker (She'll do it even when I'm going to the till), she will say shit like "Speak up leaninuk no one can hear you" in front of many customers when I'm on the till, say "GET OFF THE TILL AND GO DO SOME WORK" In a demanding way. This may seem like some petty shit but it's all adding up, she won't do any work and tries to demand me to do shit like put items into the back of the store when she needs to do it, or go onto the till when I've already answered it 100 times and she's doing fuck all.

Another coworker is 28 and on the same wage as I am, working at the place for 3 years, and is most likely trying to be promoted or some shit so is really "trying hard" at this job e.g. He will put items out like his life is depending on it. I'm 100% sure this guy has some personality disorder such as narcissism/sociopathy as I've dealt with so many people with them and he's for sure on the spectrum for them. We are both on the same role (Customer Assistant) but this guy loves to tell me what to do, for instance he saw that someone had dropped and smashed a glass of tomato sauce on the floor and instead of going to clean it up he will come over to me and tell me to clean it up, or he will give me the worst jobs and other people better ones. This guy for sure doesn't like me and talks about me behind my back calling me a bitch etc. He would never say it to my face as he knows that I train mma and would destroy him in a second. Instead he will use passive aggressive tactics such as "Yesssss matee" and then patting me on the back, this isn't on some friendly shit but more like he is trying to get physically dominant in a way.

I also overheard a supervisor calling me a "loser" (Not the exact words but it's the UK translation of pagan/wasteman) and I'm not sure what to do in these situations, should I be say something like "What was that mate?". There is also no HR as the manager here is very close to the supervisors and also its such a shit job it would be hard to find a replacement.

I'm really not sure why this shit happens to me, sometimes I feel like its the way I look. I literally say hello in the morning and go do my work.

It's hard for me to understand these situations because if this was any other place like in the streets, a party etc. I would be confrontational and shut that shit down in a second. Is there anything I can try to change about this or is my position in the "Heirachy" already been secured. I am going to university/college in 8 months so I figure I'm just going to try and grind it out until then and focus on lifting/training but would it be worth finding another job?