ADVICE NEEDED

having a hard time figuring out if the lower back pain i have, as well as the back and forth sore stretchy feeling in my sides; may have anything to do with a possible pregnancy. my last period was so light, and only lasted four days. was also sooner than usual. i've had a certain time for menstration and last month was the first month it came early. i've read soo many threads on these things and i just want someone to clarify if how i am feeling is anything close to what i think it may be.