Teething or sick? Please help

Sunday hubby, baby and I went out for dinner and got a blooming onion (fried onion pieces) along with the rest of our dinner. About 3:30 the next morning he threw up. I assumed this was because 1) teething 1 year molar #3 poked through 2) sensitive to the onion which was new to him but he liked it so I let him eat it