Going further than before

Yesterday was a really amazing and incredibly difficult work out with K.  We did two different exercise sets each with 3 reps each.  The first set was 5 exercises all working on upper body with barbells and one leg exercise it was really hard, I don't think of myself as strong and by the second rep I was shaking so bad. I had to stop between each rep to relax my muscles and stop the shaking.  The second set was a blur I was so exhausted by the first set that I couldn't believe that I had to start again and was very overwhelming.  I got the first to reps done and K said we were going to do each exercise until I could not physically not go any more...wow! Lat I doubled what I normally do I did 40!! I couldn't believe it, the step ups, crunches, weird pulley thing were okay I got about 10 more of each...but the plank I killed 1 minute! I was so so so excited because the plank is a mental exercise as well as physical. When I was doing the plank(s) I was telling myself you have faced much harder obstacles than this, mind you it never feels like it in the moment, and you are doing this for a reason and every bit of hurt is worth what I will get out of it.  It was amazing how that change of mindset allowed me to push further than ever before. I want to remember this everyday, not just in the gym and learn to find the inner strength to fight through anything that life throws at me.