What Causes Small Dry Spots On The Penis?

Hey there. I'm 21 years old and I have had unpretected sex with a partner now for about 4 months. I've noticed now that I've been having a wierd thick white paste being emitted from under my foreskin. Also, I have been having weird dry spots pop up and dissapear near the top of my shaft. I was wondering if this was a side effect of thrush/smegma? or should I be worried it is something else?