DD (19 mnths) sleeps OK and normally when she wakes I can settle her in her cot by doing some gentle hand holding and CCing. Just the last few nights though she's been waking and has been so much more angry/upset than ever before when I leave her to cry. Each time I go in she's sitting holding the bars of the cot and headbutting it as hard as possible over and over again. The first time she did it (2 nights ago) was at bedtime and I let her until she went to sleep but the next morning she had a huge lump and bruise on her forehead. When she started doing it last night I just couldn't let her so picked her up. She calms down but I can't put her back in without the same reaction so she's ended up sleeping with us. I'm so aware of creating a really bad habit but while leaving her to cry is one thing, leaving her to injure herself is impossible. She is teething horribly - could it be this and will it pass?? Or by letting her sleep with us in lieu of cracking her head open am I creating a bigger problem?
What should I do??!