My work experience is almost entirely with smallish companies, up to about 250 people, tops. I've also had the great fortune to have very large companies as clients (10,000+ employees), with engineering teams topping 100 people for a single project.
One of the things I've learned is that when you have 100 people on a software project, you get to have specialists. You have people who are really great release engineers, or SCM management types, or build engineers, etc. On smaller teams, we don't get that.
Instead, we get the guy who is "the closest thing to" the job we need. For example, I'm no UI designer, but with one of my teams, I'm the closest thing to it. That means I get to cut the images for the website. Am I as good as someone who does this and only this? Nope, but I'm better than anyone else on the team. So I cut images, and I'm glad to do it.
It's one of the hardest things to learn your first time on a small team: you aren't perfect, but if you've got some background in the area, you may be the closest thing we've got. Congratulations, those tasks are now yours. It makes for an incredible learning opportunity, and can expose you to many different aspects of software engineering. So have fun, accept that you'll be doing things that aren't easy for you to do, and learn. Maybe you'll find a new natural talent!