Oh definitely! Even as somebody who loved to draw and drew a lot already, when I first started drawing comics, it turned out it was really hard!
You have to draw a bunch of fairly finished looking illustrations where all the characters, places and objects look consistent in style and design while probably having to draw expressions or poses that would never come up in a single pinup. You'll have to draw people interacting with each other (hard) and types of people or objects that you can easily avoid drawing or just not think to draw if you normally draw pinups. A common one I see artists tripping up on is older characters or kids; a lot of pinup artists only draw young adults and teens, but then they'll need to draw somebody older like an old wizard who gives the hero a quest and it'll come out looking really obviously like they've never drawn anything like that before.
The main thing you need is just practice. Making comics is the best way to get better at comics. They will push you out of your comfort zone, so be understanding that you're pushing yourself and it's going to be hard at first just to deal with all the new things you need to draw.
Don't be afraid to look up reference images for the things you need to draw, or to find 3D models you can use as a guide for tricky objects, environments or poses. You're not less of an artist for not building all your perspective 100% from scratch all the time.
And remember that the most important thing is readability, not prettiness. You can develop polish later, and learning to draw fast means you improve fast. Focus on blocking in strong poses and contrast that clearly get across what's happening and how people are feeling; you can worry about making it all shiny and neat when you feel confident about drawing your basic characters, backgrounds and the like quickly and getting in important details.