there's a couple of things you can do easily to alleviate this.
Firstly do an infusion overnight for up to 3 nights with an anti-inflammatory gel (eg diclofenac sodium) that you can buy at the pharmacy. put a blob of the gel on the inflamed area and cover it in plastic wrap and tape it down (like sealing the gel in like a blister) and leave it overnight. Then in the morning wash it off. It might make your skin flake a bit but shouldn't be harmful unless you have allergies. That will help initially. Then for longer term management you need to stretch your adductors and hamstrings.
Stretch your adductors by side lunging stretches.. eg if you're stretching your right adductor you place your legs apart in a side lunge position and lean to the left with your right leg straight
and then you should stretch in a variety of positions to target the whole adductor and hamstrings groups... move the straight leg 30, 45, 60 degrees to the front, until your leg is forwards and you are in a standing hamstring stretch pose.
hold each stretch for 2 minutes (you need fibre lengthening, not just a short elastic response 20sec stretch) and release each gently. they should be firm but not painful to hold and do them 2-3 times per day. let us know how it feels in a week or so.. good luck :)