Greetings, sorry about the pain.
Going by your statement you are having a strained hamstring muscle.
Next Steps
you stop running for at least 2 weeks. give ice for 5 min twice a day for one week. do adductor stretching like sitting in butterfly pose if possible, if not do this after a week. you can also simultaneously visit a physio for trigger point release.
Health Tips
resting after 2-3 weeks will help heal hamstring strain. let me know the status. will update later.