Swimming and exercise week three

I discovered, or think I discovered, an accounting error in my swimming this morning.  I believe that I have been out of breath and mentally tired enough to succumb to wishful thinking and give myself credit for 2 extra laps these last few days of swimming.
On Monday the 11th I swam for 40:14.  I believe that I only covered 40 laps instead of 42 however.  The 40 minutes of exercise is far more important than how far I traveled, but I like to keep accurate numbers so that I can track my progress.  After swimming I lifted free weights for a short time.  Due to the age of my joints, tendons, and ligaments (not to mention the muscles themselves) I did not hit the weights with any ego or desire to impress whoever might be looking (there is a prime example of the aforementioned ego, thinking than anyone would be looking).  I did two sets of each exercise for each major muscle group, using very little weight.
After my Monday workout I could not sleep, so took one of my daughters to town for a little shopping trip.  When I got home, at around 2:30 pm, there was a message from work.  I agreed to go in and work 7 pm to 7 am although I had not slept.  Clocking out at 7:47 am on Tuesday morning, I was tempted to skip swimming today.  Knowing that I am subject to sliding down that slippery slope to sloth, I forced myself to drive to the gym from work.
While practically sleep swimming laps I began to think about the time it takes to make a trip up and down the pool.  I was so groggy that I kept forgetting to keep up with the number of laps I swam.  I started depending on my stopwatch, which was lying on the edge of the pool to count laps.  I usually freestyle the first trip up and back, then do the slower and more restfull sidestroke back up the pool each subsequent odd numbered trip.  Today I did a couple more freestyle laps before I started the slower, sidestroke, breath catching laps.  I lost count the first time during these first few anaerobic trips up and down the pool and never knew for sure what lap I was on thereafter.  I swam for 41:29 altogether and do not know if it was 42 or 44 laps.  No weights today.  After about a 7 hour nap, I am still not fully coherent.