Hi. I Am A 15 Year Old Female. Two Months

Hi. I am a 15 year old female. Two months ago I completed my bronze DofE but also sustained a very sore left groin. I then had to walk on it for 8 hours the following day with little rests and moving it by itself at night was not possible due to the pain. I had to lift it with my hands at points of the night at while walking to help it. It is still painful two months on but most of the time I can carry out my daily routine. It hurts when walking or stretching. I was planning on undertaking my silver DofE in a few months time in October and would love it to be healed by then. What have I done and what can I do to prevent further damage or pain. Thank you.