hey tired,
if you have a MAC i wouldn't be too worried then. A Mac is just as vulnerable as a PC but since its user base is so small, there is not a wide availability of "malware" like there is on a PC. Yah it is still possible, but having a MAC lessens those chances even more. While I personally could easily embed a keylogged into a picture file on a PC... it would take quite a lot of effort on my part to do the same on a MAC. I don't even know if its possible cause im not really familiar with macs in that sense but it would definitely take much much more effort. I would just use an updated virus scanner and I think you should be alright.