No — the amount you pay to enter a Combine (for example, $49 for the $1K Combine) is the entry cost to access the challenge, not a cash balance sitting in your account. You never risk real money in the Pro Levels; you're playing with virtual Bankroll funds.
Only profit you earn through Pro Level payouts converts to real, withdrawable cash. If you haven't started your challenge yet, you may be eligible for a refund of your purchase — see our Refund Policy article for details.