20 weeks and cramping

So last night before I went to bed, I had some cramping in my lower abdomen and lower back. When I was laying In bed, it became more intense and I couldn’t get comfortable and my back just ached like hell. Is this just my uterus stretching? I’m paranoid just because i haven’t had cramping that intense since I became pregnant. No blood or anything and it’s better this morning but would like some input from you ladies ☹️