Hi.. you don't really 'draw' a painting, you paint it. But.. 'I painted my painting' sounds a bit odd. I would say 'I worked on my painting last night' - in this way, 'worked' can be used to say things like.. - I worked on my thesis last night - I worked on my speech.. - I worked on the arrangements for the party.. - I worked on my project.. etc.

You can simply say "I worked on my painting last night " rather than including drew , because drawing (drew) and painting are not the same .

I was paintint the whole night. I was drawing the whole night. I spent the whole night drawing/painting.

I'd probably say "I spent the night painting"