Work on less drawings, and spend more time on each. Instead of posting two 15-minute drawings, post one 30-minute drawing. Or limit yourself to one drawing a day and spend all the time you would spend on other drawings on just that one drawing. Either way you shouldn't post on the intermediate board unless you are certain your picture is intermediate level.
drawn in 16 min
drawn in 3 min
|XOD|
Don't give up. Practice on the beginners board some more before posting on the intermediate.