Bottom half of your inner thigh is probably one of your adductors. That's a pain I had a lot after I had hip surgery, so I'll tell you a couple things I did as part of my PT that helped me.
One is to do side leg-lifts to strengthen the adductors. The way they had me do them is a little different than how people usually do them - instead of laying the top leg straight on top of the bottom leg, let it fall back slightly, so your top ankle is maybe 6 inches behind your bottom ankle. They also had me use a foam roller, just to lay on it with it under the tops of my thighs and roll back and forth, which loosened up everything. You can kind of use it on the inside of your thigh, but it's more awkward. You can also get a massage stick that you hold and roll over the tight area, kind of like a plastic rolling pin, and it can help loosen things up too. Lastly, get a reusable hot pad to use on the area after exercising or just whenever if it's bugging you. Heat is very relaxing.