I just feel like such and embarrassment

Hello. I just need to hear a little bit from you guys and if you’ve ever experienced this situation. I do investigations of Elder abuse for my job. I’ve been doing investigations for over 20 years. Today I went into a hearing and could not remember anything I was supposed to be testifying to . It made me look like I was incompetent. I couldn’t even read from a document clearly. I’m so afraid that I’m not going to be able to do my job anymore.