My first advice to you would be to read the rules for the Forum. I am a member for some time now and I have come to know that there are a lot of very helpful people here. However, before they are able to help you they need to have some information from you. Like the specifications of your system and the specifics about your storage. And describe what you have done exactly. Did you just "brutally" disconnect the drive or did you start a replace procedure (only possible with a pool with redundancy)? You yourself will be your best help and that starts with giving sufficient information so the forum members can help you out.
By the way, if you did not so already: before you do anything to change your system, make sure that you safe your configuration by downloading it to a safe place.