Why when I smoke crystal meth does my penis get really small?

When I smoke crystal meth (ice) my penis goes really small like I just swam in really cold water. Anyone know why this is?
And why does sex feel so much better and last so much longer when I smoke meth.
And why do people think that expressing their opinions on things they know nothing about is better than answering my question?

: http://alcoholdrugstreatment.info/why-when-i-smoke-crystal-meth-does-my-penis-get-really-small