OK here goes. When people shadow box they throw at their head level. your punches are arcing up. I don't know what style of stand up you do, but your to squared up. If you do muay thai or kyokushin then it's fine. The biggest mistake I saw tough is that you lack hip rotation, When shadow boxing get in the habit of turning your hips to maximize power. Your uppercuts are crap. dont just lower you hand and raise it up. Drop your body weight bending at the knees and thrust yourself up while lifting your hand and rotating your hips. I can find more problems but after watching about 15 sec of your vid I couldn't stand anymore. Keep training and slow down your punches focusing on throwing your punches with proper technique.
