Hi Ruben,
It could mean that yes you are doing something right, as in getting more links, or just that moz has recently crawled or found more links, and as result you are seeing a jump in your DA. A 2-5 point increase or decrease is not out of the ordinary
Here is more relevant info: http://moz.com/community/q/freaked-out-over-domain-authority-ranking-drop
Hope this helps!