Cat wont leave me alone

So I have heard that when an animal wont leave you alone, there is a possibility of you being pregnant. My fiances mom got this cat a month and a half ago, two months ago. For the last couple days, she will not leave me alone. I go to the bathroom, she waits outside the door for me. she will sleep in bed with me, she gets jealous when my son lays on me especially my stomach. This happened before when i found out I was pregnant with my son. had anyone ever bag this happen and turn out pregnant? (she's on my lap sleeping as i type this lol)