Trying it all over again

Spent another day in the lab today, and it was indeed energy-draining.
Been repeating the similar procedures for the similar experiment for the second time in this week, and I'm bored and frustrated.
The end result for the experiment today was slightly better than the previous day, but I was hoping for more than a 'slight improvement'.
I've altered almost all possible variables in the experiment, but everything has been unproductive.
Oh well, I'll just try it again :)