Front Derailleur acting funny - simple fix or take it in?

For the record, I haven't touched the bike - just doing initial research.

I was riding today and the front derailleur started acting funny. It wasn't shifting smoothly at all, and at one point, I couldn't get it to shift at all. It did shift a little later (after which I didn't touch it again).

I've got a SRAM Apex Compact double.

Is it a simple adjustment? And is that something I can/should do myself?

Is there one direction that works better? Put the bike on a trainer or a repair stand (if you have one) and try to shift. My guess is that it's more likely to be the shifter than the derailleur. I'm more familiar with Shimano, but in my experience the shifter feels normal, but you get noise or difficult shifting when the "message" gets to the derailleur. I wonder if you have a frayed cable in there.