Greetings, sorry about your pain. Going by your description you have muscle stiffness at calf area and to back of your thigh muscles. You developed muscle spasm, meaning muscles are tight.(trigger point)
Next Steps
see a physio and get a therapeutic massage or myofascial release done. you can also do a ayurvedic massage. in your first session you will have 60% pain reduction. Later you need to strengthen and stretch your muscles to maintain a healthy work and personal life.
Health Tips
this is not a problem to worry. get it settled right away. if any concerns do let me know.