quick question

 I'm assumimg, as I write this, that you didn't eat the working lunch.  Considering how recently you've had your surgery, I would advise against rushing in on unknown foods.  For the time being, you can measure out your required scoops of protein powder into baggies or even old medicine bottles so you can mix a shake at work.  The various Syntrax powders ( you can look them up on www.netrition.com and buy them almost anywhere) as well as EAS powders can be mixed with a spoon or simply shaken in a bottle.  I get my vanilla EAS at Walmart and it's considerably cheaper than most other shakes.  I recommend these 2 brands because they do not have to be made in a blender.  Either get a glass of water or other low cal beverage and add the powder and mix it or pour the powder into a bottle of water or flavored low cal beverage and put the top on and shake it up.  Another way to measure the scoops is to see how many ounces are in a scoop and then to measure them out at work into your beverage.

Once you are further along as a post-op, you may want to have low sugar/carb & high protein bars available.  Eventually you can have jerky, nuts, and possibly cheese or meat.  It will get easier.