And I'm not high lol
Caffeine-induced hallucinations are a known symptom of serious caffeine overdose, as are tiredness and just feeling weird. If you didn't drink much, you may have very low tolerance, deficiencies in your caffeine-breakdown metabolism, or both.
Thankfully, caffeine overdoses are usually self-resolving and only the most severe cases need to go to the hospital. If your heartbeat becomes irregular or breathing becomes very difficult, seriously consider going to the emergency room.