When Isabel shoots Kendo, she tosses the gun to her side before walking up to him. When she kneels down to remove the crystals from his back pocket, she is still holding on to the gun.
When the bartender pours Greg's drink, he empties the bottle and gets a full one and starts to pour. When the scene returns the bottle is a nearly empty bottle again. This is before Greg takes the yellow gems.
After Greg takes the yellow gem and the fire engine goes by, the girl across the street in the jogging suit generates three times. This could be bad CGI, an intended effect to show he is high, or a ruse by the director to contribute to his other reality theme.