Firstly, they don't test for THC, its the byproducts of THC that is tested for. *The More You Know*

Second, your mom is a nazi!

Finally, it varies greatly from person to person how long it lasts. 14g is a hell of a lot to smoke in one sitting, and I'm sure that the more you smoke, the longer it will take to get out.

No one can tell you, or even give you an accurate estimate of how long it will take to get out of your system. Its best not to risk it. Take a break for a bit. I find it highly unlikely your mom will test you continuously for the remainder of your stay under your parents roof.

Oh, where did he even say he was 15?