Can’t sleep

I’m 22 weeks and 2 days pregnant I haven’t been able to sleep in a week I’m so frustrated and tired I’m about to cry my 1 year old son sleeps threw the night so he is not keeping me up. I toss and turn and switch positions all night long I wake up almost every half hour it’s driving me insane I’ve never been threw this when I was pregnant with my son. Is there anything I can do or anything safe to take while pregnant. If I don’t get some sleep I’m going to lose my freaking mind. Please help me and give me some advice.