9 Watery eyes
Watery eyes are one of the most distinctive signs that something is happening in the upper respiratory tract. This is because the nasal cavity and eyes are connected with a tiny canal known as “nasolacrimal canal.” Its function is to drain the tears to the nasal cavity. If the channel is blocked, tears can’t be drained. The nasolacrimal channel is the reason why people get a runny nose while crying. Watery eyes are quite often the first sign that occurs hours before other symptoms kick in.