My penis is stuck

Hey guys when i pull back my forskin i can see that there is a thin peice of skin that is attached to the top of my bell end. i only discovered this a few days ago and have become very worried that i might have some sort of STD or STi :S i can pull my forskin back overthe bellend allmost and then before its fully over i see a large peice of skin thats attached to the smaler line at the top of my bell end, i tried to pull it away but not it just stings and i dont know what to do :S

Help me please :-(