I Found A Ibuprofen Bottle Open On The Counter And

I found a ibuprofen bottle open on the counter and and top was on the floor and everybody says they didn't take any. That leaves my 3 year old that has already went to sleep for the night. It's ibuprofen 200 mg but no pills were spilt out and the bottle was sitting up right. Do I need to be worried? I checked his teeth and don't see anything in his teeth and I don't think he could swallowed it whole.