I had got a popcorn kernel stuck in my throat and i couldnt get it out drinking water. it is now the morning after and my throat feels sore and it is bleeding a little when coughing up mucus. how can i get it out?

Drink or gargle with liquid is less likely successful to clear the stuck material. If tolerated, you can try to swallow a full mouth of food without chewing for 3 consecutive times. I used to swallow a bolus of rice without chewing for a couple times for removing a fish bone. That big bolus may pull the kernel along when passing the pharynx. You should see an ENT doctor if this trick doesn't work.

You likely moved it down already but have feelings from a sore where it was hung up. Taking a tablespoon or 2 of honey or karo, while rich in caloric value may be sticky enough to pull it off a resting place & down to your stomach.