I'm a junior software developer from a non-programming background, having finished a workplace learning programme to land this position. Since I've picked up the basics, I realise that I lack in some areas due to my non-programming background. I've been tempted to work on my personal programming projects during my lunch breaks, which I spend at my desk, but have been put off because I was unsure if this is acceptable or professional behaviour.
The aim of this is to get experience with other areas of programming by making software that I would personally find useful, and taking initiative to expand on my knowledge. For some further context, I have work on the side where I run an eBay store which sees a reasonable amount of traffic.
My question is: Is it unprofessional or unacceptable to develop my personal projects using my work PC during my lunch breaks? Does the answer change if my personal projects are of a commercial nature? (IE: Developing against the eBay API to streamline manual processes for my side business).