Please help regarding salary discussion.

Hello, I have a problem. I quoted a 17 Ipa during interview process and they offered 16+1 JB. But found out that they pay upto 23 for this role. And while talking to HR she asked twice if I'm okay with the salary. I feel lowballed myself here. Can I go back and ask for more? I'm really confused as I know could've got higher compensation. Please help.