Sleeping/Lying on back

Sa

Is anyone else paranoid about sleeping or even just lying on their back while watching tv? I’ve read so many things about not doing it but when I asked my OB she told me don’t worry about it if it doesn’t feel uncomfortable. She told me I’ll know when I’m too big to do it because it won’t feel good then. I’m 26 weeks and it still feels fine. It doesn’t feel like my baby/uterus are too heavy. What do you guys think about it