It really, really sucks when they are good little sleepers and then suddenly without reason they become little tyrants working your last nerve into the ground :hugs: :hugs:
Do you breastfeed? I found that dd was at her worse when my milk supply dropped and she was going through a growth spurt. I switched to forumla and it got better. I don't have a problem with bf'ing, but it could be that she is hungry and your milk is just not enought atm. I am not saying STOP bf'ing, only maybe try and supplement her with some formula or even start solids. I take she does not have any teeth yet.
Laaater it again got worse and after a week of NO sleep, I took her to the dr and found out that she had a upper airway infection. Gave her some anti-biotics and it got better.
She could be overtired by now, so MAYBE if you see a dr, he/she could prescribe something to calm her down so that she could just get a good night's sleep. That happend to us also and my pead prescribed this WONDERFULL medisan that helped her to sleep. Me, DH and dd got a night's good rest and it was better after that. I still use it when she has trouble sleeping and I see that she is overtired. I know some ppl might think that I'm drugging her, but then I tell myself that grown-ups use sleeping pills if they have problems sleeping, why not babies?? And if it's prescribed and you use it like it states on the bottle, there is no harm, kwim?? Just don't get anything over the counter. Make sure your pead prescribe it and use it EXACTLY like it's been prescribed.
It could also be that she is more aware of what is going on around her and that the slightest noise is waking her. It could be that she is to hot, or to cold, or have to much clothes on, or that there are a draft, or just about anything ... not much help

The thing is that you need to stay calm. Very, very hard, but you have to. Eliminate and if you really are at your wits end, go see a dr. Even if the dr tells you that there are nothing wrong, that would give you peace of mind.

Goodluck, I hope you find what is making her uncomfy.