alot of good explanations above but the simpliest bit of advice i can give you is change your stance. you want an even stance between front and back foot not back foot heavy like on the water.
yeah the bullet is correct. weighting more 50/50. also steering the board is opposite stare with you back foot on a longboard. so i guess your weighting to hard an the back foot and driving hard up wind.
lastly controlling a landboard is all about sliding and drifting. if you can control the drift you have unlocked the secret...drifting and 30+mph is an intense and special thing.