So much excellent advice here, so much for you to take in! Be kind to yourself, it will be ok it really, really will.
Your dd is following an almost identical path to my ds. He was delivered at term after a difficult pregnancy, sat unsupported at 11m, commando crawled dragging left leg at 14.5m, stood on tip toes at 17m, cruised on tiptoes at 21m.
He was initially assessed as being developmentally delayed by community paed and paed physio at 17m then put under review (at local child development centre) I knew he had cp - am a nurse and trained in child development, also have a friend whose ds has sdcp - so managed to get assessment with head physio, who is friends ds' physio, who confirmed my belief. Next paed appt a month later dx was made, he was 26m. MRI 4m later confirmed dx (tho MRI is not definitive).
My ds is now 3.6, he walked with a Kaye walker from 2, has had DAFO's and is currently in an AFO splint on the left side (is more affected on the left) has had gaitors and has a knee cosy to splint legs at night. He walked independently at 3.2yrs. Am currently posting from my phone which is taking aggggeeess so will be back later but to second madwoman I would maybe wait a couple of months until you have more info/ appts scheduled before applying for DLA the more info you have the better your case. Also check out and sign up on the cerebra site, loads of info, and request their guide to claiming DLA, I found it invaluable.
Oh and we went on to have another ds, he is now 13m and it's all fine, already had two older ds' and we are considering no5.......