The reason that she may be more tolerant of the mosquito bites during the day is that she's busy enough to not notice them but at night the itching wakes her up. Does she seem to be more stuffed up or her eyes red and/or with more "sleep" matter in them than usual in the morning. She may be allergic to something in her room. She may also have just a bit more difficulty breathing while lying down. It's also warmer now during the day. Is her room stuffy and perhaps holding the heat in from the day time?
My daughter needed a small fan blowing on her when she was in her bed all year round. She still uses a fan some of the time. She said the air helps her to breathe better and the noise soothes her. Her son is helped to get to sleep sometimes with a fan blowing on him. I have a fan next to my bed and he will sometimes turn it on for himself. He just turned 7.
When we wake up alot we don't get good sleep. You really don't know how much actual healing sleep that she gets. Perhaps you could try cutting back on the length of her naps. Some kids don't need naps by the time they are 3.
For the water, I suggest giving her a sippy cup to take to bed with her. She may not be drinking enough water in the daytime because she's busy playing. Because the temperature is warmer she may need more water and hasn't made the adjustment to drinking enough in the day time yet.
She may be going thru a phase of feeling insecure at night. Even as an adult I often do not want to sleep at night and prefer going to bed late so that I'm sleeping more in the daytime. I'm not suggesting that you keep her up later. lol But perhaps she needs some extra comforting right now. Asking for back rubs gave me this idea. Perhaps you could give her some extra time at bedtime. What is your routine? Do you spend at least 20-30 minutes with her before you turn out the light?
And would it be possible for you to wake her up with an affectionate good morning? perhaps a hug? Have you tried just holding her and rocking her when she first wakes up? It sounds like she may be feeling insecure.
Have you asked her why she's having trouble sleeping and waking up screaming? At 3 she may be able to tell you when you ask a direct question. If not you could try telling her a story about another little girl who has the same difficulty that she's having and ask her how she thinks this other little girl feels and what she would suggest that the mother do for this other little girl.
Does she have a night light? This might help. I really like the suggestion of a glow light or a toy that lights up when you squeeze some part of it. My daughter came to me as a foster child. She's been living at Waverly, a group home for children where it would be difficult to get someone's attention at night. Someone had given her a toy that looked like it may have been called a glow worm. When you squeezed it's tummy it lit up. She took that to bed with her for several weeks. Then she graduated to a stuffed clown that I had put in her Easter basket. She still has that bunny sitting on her bed. Having something cozy to hold often helps little children and big feel more secure.
I'm with you. I definitely do not like getting woke up in the middle of the night and especially numerous times. And if co-sleeping doesn't work for you something else will. I could not co-sleep with my daughter when she was a foster child. It's against the rules. Sometimes I cheated and it did work. When she slept in my bed she slept thru the night and so did I.