Sounds like food poisoning to me…
How cooked was the meat when you ate it? Was it more on the raw/rare side?
Have you been eating meat in general before this dinner?
I eat lamb 1-2x per week and have had no problem. I know you probably don’t want to do this, but try cooking up some lamb at home to see if you get the same reaction. If so, then the cause could be because of other reasons.