I feel worse after a nap

In short: this happens to many people. A nap does not always “reset” you. Sometimes it triggers sleep inertia, and waking up feels heavy.

Common patterns:

• the nap was longer than you intended
• you woke from deeper sleep
• the nap was late and shifted the evening
• your baseline was already low, and the nap was a marker of fatigue

Your wearable may log the nap as sleep, or it may miss it. What matters most is what happened to the evening and the night.

If you want the full picture: Napping: how it affects night sleep and recovery.

Related short answer: A 1-hour nap - is that normal?.