my lawyer double billed me $40,000.00 to $80.000 and wants to sue me now for all $80,000.00 and there is no fee agreement

i did not pay my lawyer bill when after two weeks i recieved a bill for $40,000,00 for his service Now he has proformed no other service for me Now he Doubled his bill to $80,000.00 and will take nothing less than $80,000.00 now he is going to sue me if i dont pay alll $80,000.00 or sign a payment agreement to with him i feel like iam being strong armed there is no fee agreement i never signed one on top of this i have already paid him $30,000.00