My first job. Hired as a designer. It was me and a backend dev (PHP). Company wanted us to build their e-commerce website, but the backend dev had no eye for design or front end chops, fell onto me, so I learned it on the spot.

I also did the mistake of trying to prove myself too hard and ended up doing IT, network and user support, user training, phone sales and helping the print team on designs, on top of my already taxing responsibilities, for 18k/year.

In the end, the company moved offices and I was tasked with finding and installing a new server, IP phone system, and organising the desks following a carefully crafted and approved plan. Spent the weekend doing that (had some friends that didn't even work for the company join as they knew of my struggle) only for the bosses to arrive on Monday, decide they didn't like it, and just said "change it", ignoring the plan entirely. I then left without having another job lined up and never looked back.