So I have this coworker who's been at the company for 20 or so years. I'm very new at the job but I have already decided that I want to leave when my contract ends. I just don't like it there and I plan to change careers and get into another field. Better to start new while I'm still kinda young than to work for the rest of my life a job I don't like I guess. 

Anyway, this coworker seems to always criticizes me. And not in the fair, constructive way. Always with a very upsetting tone and like "You're here for so and so months now, you should know better!". It's true that I make mistakes sometimes, but so does he and everyone else, but it seems that it's only when I do a mistake it becomes a state affair. It's been like that from day one. The first time I was there he asked me if I have any experience on the job at all. I said no and he just shook his head in disappointment and went his way.

He's not always that bad, sometimes he's nice but he always seems to have me as a target.

So today I did a very minor mistake, something that maybe took 30 seconds to fix. He came up to me and said how disappointing I am and that I don't have a future at the company. That enraged me somehow, even though I plan to go anyway. It was just that disrespectful tone towards me. Anyway I started to tell him that we will see what my future brings and that it's not his decision if I stay at the company or not and that we can talk with the supervisor. Luckily enough the supervisor came in just as we were arguing and at that point I got loud and just told the supervisor how this coworker is getting on my nerves since day one, how he's talking behind my back, how it's somehow always just me that in his mind makes mistakes even though others do them all the time as well, him included and so on and so forth.

He stayed rather calm and just poked fun at me, how I can't take criticism, how I always make mistakes and don't learn from them and all that... It felt like I was in a film. I 100% don't make more mistakes than anyone else at the job and yet he singles me out.

Sorry, just venting here.