Today (11-September-2019) at 09:42 UTC a magnitude 3,0 earthquake took place in Hengill volcano. The largest earthquake was felt in Hveragerði village. They also felt a minor magnitude Mw1,7 that happened at 05:22 UTC. The reason why that earthquake was felt is because it took place inside the town under some person house (or close to someone house).
The earthquake swarm in Hengill volcano today (11-September-2019). Copyright of this image belongs to Icelandic Met Office.
Earthquake activity is a regular feature in this area.