welcome to HealthcareMagic
The light cramps you say may be due to ovulation as you feel but normally during ovulation there is no pain and there may be just a bit of increased discharge vaginally.As for the nausea
along with the cramps it can be due to gastritis
and intestinal pain also and definitely not due to pregnancy
as for pregnancy you will get symptoms only after the missed periods or at least after the due date.