Hang in there!
Things never change - when i started 22 years ago, the experience was the same - get up, fall on you ass, repeat. Some padding in the back of your pants helps.
It gets a lot easier after about the fourth day and the learning curve is a lot quicker than skiing. I helps to warm up on the bunny slope with basic moves - ollies, wheelies, tail/nose roles - the helps with board control and is a good warmup.
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