Clonazepan SOS

When do you know is time for take it? I was eating dinner with my husband and everything was great until k started feeling a numbness in my hands, my brain was going super fast and also intrusive thoughts, I know those are my symptoms when the panic attack is about to happen, took my pill immediately but it have passed 20 minutes or so and i still feel weird, not feeling comfortable in my body. Is that normal? How long it takes to stop it?