So in the past week, I've noticed that At night time I've been getting bad back pain to the point…

So in the past week, I've noticed that At night time I've been getting bad back pain to the point where it hurts to move. I'm not really sure if it's normal or not since this is my first pregnancy and I'm having twins. It doesn't happen every night just sometimes and it can sometimes only last for a few minutes than stop. Idk whether to call my doctor or just wait until my appointment (next Monday). The babies are kicking like crazy so I don't believe any things wrong. But I'd rather be safe than sorry.