toddler sleep

How do I get my toddler to sleep?!? My daughter is 15 months old and will NOT sleep! We switched her out of her crib to a toddler bed (because she woke up 3+ times a night still) she was doing great in it, slept basically all night, would lay down on it and get herself to sleep ect. Then she just stopped sleeping all together but is soooo tired! So now not only has she not slept for a week, but of course mommy hasn't either and the lack of sleep is causing major temper tantrums that pregnant me is having the hardest time dealing with. She started out just not taking her naps. which I thought at this age no big deal her sleep needs are changing since she's finally resting at night we'll work together and find another nap routine. she was fighting me to sleep(which she never does) and would scream(literally) and smack the entire time she waa as "sleeping so 30 mins of her fighting now She's not sleeping at night either she keeps fighting, crying out, screaming, getting up and nothing I do can help her, I even tried putting her in the bed with us thinking maybe that would help the nightmarish behavior and calm her some. Idk what else to do or how I'm going to handle this and a new born in Nov/Dec if I can't get her back sleeping.Has anyone else went through this??? I know the doctors keep telling me it's impossible but I feel like her febrile seizures changed her. She never acted like this before, not slept well yes, but that was because she wanted to be snuggled, now idk what it is. Add that to her new temper tantrums and I just am starting to feel helpless...