Ontel Handy Heater Compact Plug-in Personal Heater with Digital Display, On/Off & Timer

I didn't realise it was bulkier than expected. My plug is just about 6 inches off my bed. It won't fit. I wonder if it would be ok to use it sideways?? Plus the plug came with 2 round prongs instead of 3 and it says in the manual don't use an adapter or extension. Hmm...Edit: I plugged it sideways because there's no way it would fit. After only about 15 mins, a part of the grill vent "melted". Not completely but you know how a plastic melts. It didn't smell anything funny but just the deformation after about 15 mins.