I'm sorry if this has been asked before but I get so tired after eating and I just want to know if this is normal? The yawning starts so quickly after eating and sometimes I have to actually nap. This ok when I'm home but it's an issue at work.

Any comments greatly appreciated

Yeah happens to me all the time!! I try and keep meals smaller then not as tired. But sometimes can't help it and I have a nap.

Honestly, this sounds like high blood sugar--or higher blood sugar in response to a meal. You should buy a glucometer and strips and test before eating, then at 1 and 2 hours after a meal to get a picture into what is happening.

Try the "grazing" method. Take a bite of food, then go do something, then come back for another bite.
I used to keep mixed nuts at my desk. In my job, I needed to be away from my desk quite a bit, so I'd take a few nuts and go. Keeping some hidden in the back of your desk drawer could work, too.
I also recommend getting some Trim & Healthy Mama Integral Collagen. It has no flavor, is high in protein & you can put it on or in anything. It's good for your bones , nails & hair, too.