What Do Cramps,lower Back Pain And Nausea Indicate?

i'm 25 and have been off the pill for 2 months, i havnt got the usual sore breasts before my period , only less painful cramps on the right side and some tingling since 6 days past ovulation, some lower back pain and the odd wave of nausea. i feel like my period is coming for the last few days but has only been a little watery discharge. also i didnt dry up mucus wise after ovulation. do you think its possibly pregnancy or just hormones?