Stomach Bug Or Allergies

The past couple times I have had beef I had thought I was gaining a sensitivity to it, but unsure.  Two nights ago we had a roast for dinner, it was lovely.  However that evening I was nauseated, and then the next day sick.  But also couldn't keep my eyes open if I tried, dead tired.  First thing in the morning Deb was getting ready for work, I was hugging the toilet and Spencer needed attending to, so we called in the help of Yaya.  She came over and fed him and played with him till his nap at 9:30 and I napped as well till he woke up.  Spencer was a peach that day and wasn't fussy at all, played quietly in his exersaucer or playpen etc.  And relatively went down for naps without commotion.  I got some additional Yaya assistance in the afternoon, while I napped again.  By afternoon I was able to keep down a piece of toast and water.

Update: Spencer got sick two days later so I am guessing more of a bug. Poor little one.