Don't play when tired!

I have only been playing and learning for a month or so but already I am learning that sometimes you can try too hard and practice too much. for example: Two nights ago, I took part in a Freerole NL tournament with 12,000+ other pker nuts. I had been reading up on Strategy, playing in two other mini tournaments and also on or two $0.01/0.02 cash games during the day. (I am obviously well and truelly hooked). Anyway, I started the tourney, determined to get through to the money, if I could. I did. I finished in 661st position and won a whole $0.07 I was extatic. I had come in the top 5% and had only exited then by playing a hand I had no business playing and refused to put down even when I KNEW I was being suicidal!
I then played in a further tourny a few minutes later...and was wiped out within minutes, for playing like an idiot. I acted as if I had never read a single word of strategy. A complete novice! I was tired.
That was then.
Last night, I decided to do better. I still read up on strategy, still played a few cash games during the day and still did well in the big tourny, this time finishing 111th out of 6,063 players (top 2%), and winning a further $0.07. I was confident or is it competent enough to recognise that I had played 6 seperate hand badly during those hours of play and can even remember the cards, my position on the table and what I did wrong. I was again, very pleased with myself. (What is it they say goes before a fall?).
So I went on to another tournament...and was wiped out within minutes, then to a cash game, and was cleaned out in minutes; again playing hands which I had the wisdom to know I shouldn't, the skill to lay them down but a total inability to do anything other than act like the proverbial rabbit in the headlights.

Don't play when tired! Don't play when tired! Don't play when tired!
I am saying it to myself now...all day long!