Hi, I Was Just Curious Of Why My Nose Drips

Hi, I was just curious of why my nose drips a clear liquid. It taste metallic and is like a rain drop. I didn't know if it was just a cold, allergies, or something worse. I've also been experiencing headaches. Nothing to unbearable but just enough to know it's there. I hardly ever get headaches though so I'm just paranoid about it.