What Causes The Infant To Continuously Grab Its Throat?

My 16 month old has been for several months grabbing at his throat. It s sometimes often throughout a day and sometimes even while standing to the point where he s a little out of balance and stumbles a little. Doctor checked it at 12 and 15 month but was really quick he said may just be a tick? I m scared I just worry wanted another opinion but we re moving haven t gotten one yet