I got a job opportunity in another country and went there for a 3 weeks trail working, I've worked on two different projects, one was with a CMS called Contao and the other one on WordPress, I'm fluent on WordPress, I've been developing themes for more than three years now.
With Contao I started the learning curve and for 2 weeks I learned a lot of stuff.

Before coming back for Visa stuff and taking care for few documentes needed they asked me if I could still do some freelance stuff from my home country. I said yes and got invited to the GIT repo.

It's been a week now that I'm trying to understand how stuff work and everything that the senior dev wrote is way advanced from everything that I've ever worked.
I couldn't finish more then 5 minor tasks simple CSS and PHP logic and I'm feeling very embarrassed.

I just wrote to the senior dev and told him that I'm way behind with my coding skills and I'm seeing dreams with code that don't work.