Afraid my supply is running out and I will NOT use formula

CJJ1016

Hey ladies-

 DD will be 12 mos. on the 24th and has been nursing from the start. She also eats some solids during that day (usually 1 jar of baby food, a baby mum-mum cracker or 2, and munches on baby carrots). She nurses all throughout the day and nurses to sleep at night. 

I'm afraid that my supply may be steadily going down, she can't have cow's milk for another month and I won't give her formula, so what to do at night? She's been super super fussy before bed because of the no milk thing but doesn't want water.

Help?