You're asking a wise question here. The way that GMAT scoring works is a little hard to wrap your head around, but the images you've posted are a good example of what most test-takers will see as they improve. (By the way, 32 to 42 is a nice improvement -- excellent work!)
First of all, check out this article:
https://www.manhattanprep.com/gmat/blog ... mat-quant/The GMAT is a weird test - on a traditional test, everybody takes basically the same test, but some people get more questions right than others. On the GMAT, everybody effectively takes a different test, but gets roughly the same 'grade'. As you've seen, there is a small difference in how many you get right/wrong at the very low end and the very high end; people with very low Q scores, like your initial score, will typically get a few more problems wrong than people with mid to high scores. But there isn't a very wide range. Instead, the GMAT makes the test harder or easier until you're missing about half of the questions, and then gives you a score based on how hard your test was.
The numbers show that your second two tests were harder than the first one, so you're heading in the right direction!
However (there's always a however...), be careful about your accuracy on the lower-difficulty questions. Ideally, I like to see close to 100% accuracy on the 'easier' questions, regardless of what 'easier' means for you, before you start working on the harder questions. Getting one or two super-tough questions right does very little for your score, but missing an easy question is particularly bad for you. Look out for those careless mistakes