To have or have not a mirror....

I am back on track with my exercise. I am at Cha's house and she has thi awesome mirror that runs along the living room. I have been doing p90x routine for about 6 weeks and I assumed my posture was correct. I worked out ro max capacity today. I wanted to puke. Because I was looking at myself in the mirror and I was able to see my form and when i saw that my form was bad or that I was slacking I told myself to kick it up. I felt fatigued but glad I worked out. I really do enjoy it. Plus I can have some carbs now.... till tomorrow