My masternode shows as active when I run "masternode status" command and also appears in
https://masternodes.pro/stats/xmcc as an active node for 4+ days now.
When should I expect to receive first payment(s) and/or should I be concerned something is not working properly yet?
There are several statuses as NEW_START_REQUIRED, ENABLED, OUTPOINT_SPENT, WATCHDOG_EXPIRED, EXPIRED. Check what is the status of your node. Also, check if the command masternode outputs is still giving you something as output and not empty output.