Keep doing it. The more you do it, if you are paying attention, the better you will surf. In surfing, a willingness to get wiped-out is essential to improvement. The best surfers usually suffer the most horrendous wipe-outs. That's what it takes to push to the next level of skill.
Higher skills are harder to learn, and the penalty for failure is swift and sure.
Accept it as part of the game. Good physical conditioning is essential to paddlesurfing enjoyment. It can be a rough and tumble sport, and requires both strength and endurance to attain a high skill level. Like there are all levels of proficiency in paddlesurfing, there are also numerous craft to correspond to these levels. A length of 11 feet or shorter is preferrable for manuverability.