Pregnant After Rejected By Alpha

When I woke up, I was  and lying on a soft bed that wasn't mine, being held by a stranger whom I absolutely didn't recognize. 
At the same time, there was an intense pain between my legs, I nearly screamed out loud. 
Did I give my virginity to an unknown man?!
****************I am the youngest daughter of Silver Moon Pack's Alpha Aiden, and I have a twin sister. We look alike, but our destinies are completely different. 
She is a female warrior and is known as the next Alpha, while I am an Omega who cannot shift into a wolf, which is considered shameful by the Pack and my father. 
For 18 years, I have been guarding my virginity and waiting for my mate to appear and take me away until Blood Moon Pack Alpha's birthday, I had a one-night stand with the infamous Alpha Nicklaus, my father's enemy. 
When I found out he was my mate, I was rejected. I finally decided to hide it all, I got pregnant.