5G is designed to meet the requirements of various network services such as eMBB (enhanced Mobile Broadband), URLLC (Ultra Reliable Low Latency Communications), and mMTC (massive Machine Type Communication) by making use of the technologies such as Software Defined Networking (SDN) and Network Function Virtualization (NFV). These services can be provided through isolated virtual networks bringing in the concept of network slicing in 5G which helps in adjusting the resources dynamically which in turn can maximize resource utilization across the services. The dynamic adjustment of resources can be achieved by monitoring slice instances in the Closed Loop Automation (CLA) to make quick decisions on slice scaling, selection, etc. In this paper, we propose a Self Regulating Network Slicing (SERENS) framework for slice monitoring and selection in 5G. We have developed a prototype of the proposed SERENS framework in a 5G test-bed system and shown that proper slice selection can avoid wastage of resources of slices by up to 60%. The proposed slice selection algorithm will help the operator to serve a higher number of users while making the efficient usage of the available resources. © 2020 IEEE.