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I assume your collimation is correct.
Check you can move the focuser further in and out beyond the point at which you judge focus to be best. Adjust the focuser tension for fine focus.
Try a different eyepiece.
Compare what you see through someone else's scope, it will give you a better idea.
Focussing a star to a "pinpoint" is rather a subjective assessment. You cannot actually focus a star to a literal pinpoint due to diffraction of light. Theoretically, the smallest point of light you can get is the size of the airy disk.
In practice, seeing conditions will affect what you see more than anything else. The brighter the star, the larger the glare and the more bloated the star will look. Stars will appear as specks of light about 1 or 2 arcsec diameter. If you compare stars through your scope, they don't all appear the same size. Also, in a fast reflector you will get more coma which can add volume to stars.
Regards, Rob
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