Going forward... and backward?

This was a strange workout in terms of results. I hope it only has to do with the fact that I went for a run (4 km) two days before, and I had not fully recovered. I don't usually run, so that really took a toll on my body, even though the timed result from the run was actually not that bad, considering I hadn't done it for a while (23 minutes is my record time, this time I did it on 24).
However, looking at the graph, the results are still pointing upwards in total. It looks more as if the previous workout had some really high values.

The front pulldown was really really bad this time. My lower arms just died, and I couldn't continue. The grip felt really unnatural. I think I need a more tilted grip, rather than a straight bar like I used this time.
The benchpress was far worse than last time, but better than the time before that. Hmm.
As for the seated row, I increased the weight, but the calculated amount of work was the same as before, so it's hard to tell if I progressed.

On another note, I bought a digital scale for travelbags, and used it to measure the actual weight of some machines, and bars with fixed weight marked on them. Some machines actually show the correct weight, but most don't. No surprise there. A surprise was that a barbell with fixed weights that said 17 kg actually weighed more than 18 ks.
So what I will do is start using the real weights, so that I can somewhat reliably follow the results produced in two different gyms with different brand machines.