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It would have been better if you hadn't moved the secondary mirror, as the secondary is meant to be slightly offset in short focal length telescopes. But maybe it doesn't matter - since you can easily see the entire primary in it, the secondary may be a bit oversized.
To get the position of the secondary correct, it is more useful to have a long tube with a peep sight in one end and with cross hairs at the other end. You can easily improvise, using your current eyepiece without the lens, getting a Barlow and unscrewing the lens from the bottom, and temporarily sticking some hairs across the open base to make cross hairs. Use the eyepiece in the Barlow tube with the cross hairs to make sure the secondary is in the right position. After you've done it once, you never have to do it again.
When you throw a star out of focus, do you see concentric rings around a dark dot? If your telescope shows this, and the dot isn't dead centre, you have to adjust it to make it so.
However, my f/4.5 dob doesn't show the concentric rings, so I made a an aperture mask for it with circles cut out that fitted where the mirror was clear (between the secondary and the primary's outer edge). Then the concentric rings around the dot were easy to see. But even when concentric, there is a slight flare to one side in the direction of outer edge of the primary. It is then a matter of rotating the mask around, making sure that the out of focus image in each of four positions around the diameter is the same (i.e. each is concentric with its little flare the same length pointing to the outer edge of the mirror).
If you get say three images correct, but one not right - suspect pinched optics on that side.
This aperture mask technique (which you make up with cardboard or plastic from a folder) always shows where you are out. I remember looking through an 18" telescope and saying it was way out of collimation. The owner replied that it couldn't be as his laser said it was perfect. Fortunately he had an aperture mask handy which I used to show him how hopelessly it was out of collimation.
Good luck.
Renato
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