lost voice

So my 11 month has been attending daycare for the past few weeks , she only goes on Tuesdays and Thursdays so she's only gone a total of 3 times so far. Well last Thursday I dropped her off and headed to work that day for some reason I did not think to call to check to see how she was doing , I worked late that day so I asked my mom could she pick her up , my mom was stuck in traffic so I called my daughters teacher to let her know she was going to be late , my mom said she was 20 minutes late the teacher charged me a $65 late fee which is extremely ridiculous!!!! Well the following day I noticed my daughters voice was a little raspy I didn't think anything of it so I ignored Saturday we woke up her voice was completely GONE!!!!! It's Sunday and my child's voice is gone she can't talk cry nothing , she hasn't been sick so the only thing I could think of was the daycare possibly letting her cry for too long?!! My heart is broken hearing my 10 month olds child's voice gone , the way I'm feeling I really want to do a full on investigation to find out if my child was left crying for hours I need advice what should I do??