Hi, My 17 Month Old Has Swollowed Baby Oil. I

Hi, my 17 month old has swollowed baby oil.
I had my back turned fot literally about five seconds and it was gone from the side and tipped upside down in his mouth.
I dont know how much, it could have just been a few drops but when I tilped it upside down it came out quite fast.
He did a couple of little coughs like the taste was horrid and hasnt coughed since.
I called poison controll and they told me to monitor him but since then I have read that it can cause death. I am now extreemly worried.
This happened this evening so I kept him awake as long as I could and am now sleeping with him.
Do you know the signs I should be looking for? How could I know if its fatal? Should we go to the hospital?
Thank you for your time
:)