What's the problem?

My fiancee mother is over and she made a comment when was I gong to make her a grandmother,and I told her that where TTC,and I have a doctor appointment this Tuesday.I told her since I lost my baby in Jan of this yr at 21 weeks my cycle has been whacked after the d&c.The last 2 mths I've been coming on twice.Now I know my fiancee did'nt tell her about me loosing the baby,he never told her I was pregnant because he wanted it to be a surprise,that would've been his 1st child.But after I told her about what happened she stop tlking and got quiet.Like she was in deep thought or better yet she had a look on her face like I did something wrong.I don't know but it's a real FU*CKED up look on her face.What could the problem be?