14 month old Waking up screaming

So to start, my girl has always been a great sleeper but lately, after putting her to bed, anywhere from 30 min - 2 hrs later she will wake up screaming. I let her cry for about 5-8 min to see if it’s getting worse or if she will self soothe. Then I go in and try to rub her back or hold her. Nothing works. She pushes out with her legs and arms pulling away when I hold her, but won’t calm down when in bed (she crawls around, sits, stands, crying the whole time). And her cry sounds painful. High pitched and so sad to hear 😢 funny thing is when I open the door (and a bit of light peeks in) she cheers up a bit. I always end up popping her back on the boob to cheer her up and calm her down but i would rather not get her in the habit. Any ideas of what it might be? I thought teething but the isn’t rubbing her teeth or showing any signs at night that they’re hurting her.

Ps: once she’s asleep again, she’s fine the rest of the night.