Extremely tiring day

I ran 10 rounds during PE, clocking 19mins 46secs. I consider it satisfactory as I've not run for about a week already. The last time I ran a clocked 10 round circuit was last yr during PE in NJC, and I clocked 20mins 20secs or so. I've improved only that little bit. :( For the rest of the day, I was exhausted. I couldn't really concentrate much during lessons. I had a flight later that afternoon, and I knew the fatigue would affect me.
My lessons ended at 1.15pm and I had to reach SYFC by 1.40pm. Thus, had to spend $8 on taxi again. I really did badly for today's flight. By the third or forth circuit, I couldn't concentrate at all, my mind was drained. I made several errors such as letting the plane drift, and being inconsistent on my final approach to land. The instructor said I must work much harder for the next couple of flights if I want to go for my first solo flight.
The 4KM run made me physically exhausted, and the flight drained me mentally and morally... that leaves me with nothing, haha.