I've been feeling really strange lately. I have been getting waves of nausea throughout the day, headaches, sore and heavy breasts, been more tired than usual, and a strange feeling in my lower abdomen. I was wondering if you could tell me any possibility as to if it's a pregnancy?

If you are female and have had sexual intercourse, yes.
But as we say dozens of times a day here, there is no way to know ONLINE. Take a test.
If you test negative, see a doctor about other conditions.