HHC Withdrawal
A classic physical withdrawal like with alcohol or opiates hasn't clearly been proven for HHC so far. But some users do report feeling restless, having trouble sleeping, being irritable, or having strong cravings after regular use.
How intense these symptoms get mostly depends on how long you've been using, the dosage, and your personal disposition. Taking a break and being mindful with your use usually helps your body get back to normal.