Pain in lower leg/shin area

I have been experiencing some pain in the lower leg/shin area for some time now. At first it was after I played basketball for some time and it felt like my calves would get really tight. Also, at times my feet would become numb and “fall asleep” while I was playing. The pain became really bad, hurting mostly when I tried to walk but I was able to run once I got going and the pain was not there. Now, I am experiencing it more frequently and the other day it became very painful while playing softball. Again, I was able to run fine but when walking back out to the field and so on my the front of my shins seemed to get really tight. It hurt to walk and my calves seemed to tighten up as well. Can anybody help?