Hey guys, new to the forum!

I've been an avid runner since middle school (10+ years), but now that I'm out of college I was looking to broaden my workout routine, so picked up my first road bike! It's a Specialized Allez Double, and I've had it for about a week.

I took it for my 3rd ride today, and about halfway through the trip I was in my higher front gear (of the two) and pressed the little black button (Shimano Sora shifters) to downshift my front derailleur. Unfortunately, it would not budge. I had to ride home stuck in the 2nd front gear.

I've got lots of tools, but don't know where to start. The shifting mechanism (in the handlebar, not at the derailleur) seems to be jammed, but I don't know if this is something that can be easily taken apart/cleaned? Thanks!

(The shop I bought it from is fantastic, and I'm sure they'll fix it free of charge, but if I could save myself a trip and learn a bit about the bike in the process, I'd love to.)