How can i get her to sleep? 7Month old, Sleeping Problems.?

[kayleigh]

My 7Month old daughter refuses to go to sleep at bed time, She has been in a routine of going to bed at 7 and waking up at around 7-8the next morning. She got herself in this routine when she was about 2months.
Recently, When i put her to bed she screams, As soon as i pick her up she stops, when she is put back in her cot she screams again. Ive tried leaving her to cry it out but i cant handle it for to long (She screams for ages) Ive tried sitting in her room, going in, not talking laying her back down and giving her dummy back nothings working. She also refuses to nap and now wakes up at 5-6 in the morning. She is so tired all the time bless her, but she just refuses. Any ideas?!