You know as a senior marketing professional I can relate with your concerns and how people feel during their initial stage. I can give you a tip which will come in handy for you in the future- Never achieve 100% sales target else they will increase your next target immediately. Keep it around 90-95% which is enough. Also make it a rule to put your company 30, your clients 50 and yourself 20% beneficiary because you might change a company but clients will be yours forever. All the best.