I did gunpowder too, besides making lots, including experiments in corning it. By far the most dangerous things I did in this line!
Nitroglycerin is ... ambitious!
It was and my dad wasn't pleased. I walked it to a nearby canyon and detonated it from a safe distance with my BB rifle.
My dad confessed to sifting flour in front of an electric fan and lighting it off in his own garage. His punishment for blowing all the windows out was replacing them AT HIS EXPENSE. Hours of cleaning up broken glass, chipping out the putty from the 8"x 8" square panes, cutting replacements and place fresh putty in, then repainting. The lesson was learned. The mistake was not repeated.