Little Movement

I'm 20 weeks pregnant on Sunday, I usually feel little kicks in the morning, after lunch, and at night or when I lay on my back. I haven't felt any kicks today, and I got home and laid on my back and still nothing. My cramping has been AWFUL since Sunday night, woke up Monday and couldn't even fully stand up without tearing up. My ob really doesn't like me calling all the time, it's my first baby after my rainbow baby. No sure what to do. Help me!!