I'm with Ashton on this one..
DUDE WHAT WERE YOU THINKING!!
You never took physics did you?
AND you lied to your mum...
Fudge mate.. I try to keep the nominal as possible.. like small things.. but anything that involves money...
Ok well.. try to rectify the 'trust bond' between you and your mum.. cause they can be the.. they can be.. um.. they're your mum and they're there when you need them most.