Sore breast

[Arearis]

I noticed for about 4 days now the outer side of one breast and the innner side of the other are terribly tender. It doesnt hurt all the time, only when pressure is applied almost as if it is brusied. I cant feel any lumps but then again I cant really tell for sure. I am almost 23 and I have never had any kids, nor I have I ever experienced breast soreness at all even with pms. I had my period about 2 weeks ago and it was light and shorter than normal. It was also a bit late. I was worried I could have been pregnant before I had my period as there was a chance but it came and went within 3 days. Well now with this soreness I am wondering if that could have just been early bleeding or if the soreness is from something more serious such as cancer. I am worried sick over this. Today is my last class of college and I could care less because I am so worked up over this. Is this somethin I should see a doctor over or am I just letting my anxiety get the better of me.