Chequered, the lesson wasn't wasted mate... you've learned a very valuable lesson about human limitations & performance - remember,
you may be the most vulnerable component of the whole system!
Happily you have learned this whilst sitting alongside an instructor and before you have qualified, rather than in the period soon after getting your license (which you will, get your license I mean): many have succumbed to the "bullet proof" feeling of invincibilility only to find that due to some combination of external conditions (e.g. wx) and their own health or state of mind that they are suddenly disoriented or over-loaded... it's vital to be able to recognise this and intervene positively (throwing pride out of the window!) to turn back, divert etc. ASAP.
I recall one day ~5yrs ago when assigned to fly circuits with the instructor and I just had a simple head cold: I was absolutely rubbish! Low-energy, slow-brained, and uncomprehending as to why I suddenly couldn't fly a circuit right to save my life..! (well, that exagerates the situation a bit, but you get my drift).
So be happy that this important lesson has been learned - it will stay with you! Remember you must "fill the cup of experience"
before you "empty the cup of luck"...
Andy
