An annual review covers an entire year's performance, but if you've done what you should have as a manager -- had ongoing performance discussions with the employee throughout the prior year -- then there should be no surprises. She should know what to expect on that annual review document. Still, for an employee, seeing it in writing, especially if it's less than glowing feedback, that can feel like a big hit.
The issue of her recent performance misstep that you need to counsel her on is a separate (although related) matter. It should be handled in a separate conversation for two primary reasons. It happened in a different performance cycle, not during the last annual formal performance appraisal period, right? You also want to provide immediate corrective action on recent behavior and not confuse her regarding what information that went into your performance rating. Within the counseling session, you can use some of the same language as you do on the performance appraisal if she has a continuing problem with a certain skill area (e.g., attention to detail, communication skills).
Handle the corrective action as soon as possible and document your conversation. You can then do the performance appraisal later in the week. When you do the performance appraisal be clear what the evaluation period was. I hope that helps.