Is this a normal experience for a developer in the UK or is it just my workplace?

I'm in my early 20s and work for a very small UK web/software company (less than 10 people). I joined through work experience and have now been there full-time for just over 3 years.

I'm on £26k and my job title is simply "Developer". There are only two developers in the company, and this is the only development job I've ever had.

My work includes:

C#/.NET web apps and websites

Backend, frontend, SQL and APIs

Payment and membership systems

Deployments, DNS and SSL

Production debugging

Talking directly to clients about technical issues

Moving sites to newer servers

Estimating large jobs or systems

Maintaining old systems

There's a lot of context switching and I work across several projects in a day. There is no DevOps, sysadmin, QA or infrastructure, so technical work ends up with one of the two developers.

My bigger concern is how work reaches development. Projects can start with fairly vague requirements, so I often have to work out a lot of what the system should actually do while building it. More requirements and exceptions then appear later because they weren't established beforehand. I often have to reconstruct what a client actually asked for from emails, existing code or conversations other people had with them.

Because the requirements aren't defined, there isn't a proper specification to test against. Then the client uses it, says they expected something different, and it comes back as another change or bug even though the original behaviour was never clearly agreed or I had no knowledge of it as it existed in someone else's head.

I've also never really had a formal career progression. I've gone from work experience/junior level to doing all of this without there being a clear point where my role or level changed.

I know developers wear more hats in tiny agencies, but I'm trying to work out how normal this kind of experience is.

For people who've worked elsewhere:

Does this seem normal for a developer at a tiny agency

Does £26k seem reasonable for this responsibility outside London?

What level would you consider this work: junior, mid-level, senior, or just "small company developer who does everything"?