I'm leaving my baby to cry :( am I doing the wrong thing?

[JustOneMoreBiscuit]

Just reading some other threads on here little sleep after 7 months doesn't seem so bad, but I'm on my own at a lot at night and DD has had 10 really bad nights.
My arms are sore from carrying her round. Ive patted/ sung and distracted. Every bloody 2 hours.

Took her to the docs to check there isnt an underlying problem. She is teething but nothing else. She's been on calpol/ nurofen/ powders/ gels.

I'll go up now as its been 10 mins and she's still crying. I just can't keep doing this- exhausted. Tell me it gets better!

I fake it. Sleep that is. If I have tried everything and it just isn't working then I take her into our room and cuddle up next to her with my eyes closed on the bed. She kicks and plays for about 10 mins and then starts to eye rub. Then she might cry so I might open my eyes and stroke her head or quietly sing which usually results in her getting very active again but calms her down and then the eye rubbing starts again and then she falls asleep. I guess it's going down the co-sleeping route but I'm not actually going to sleep and when I know she's truely asleep I put her on my shoulder and then carry her to her cot. I think it probably makes her feel a bit more safe, she's obviously tired but doesn't want to sleep alone, that's my guess anyway.