Desperate and need help

I hate to admit that I am sobbing at I write this, but my three month old (just turned 3 months yesterday) has gone from getting up once or twice a night to only sleeping in 30-40 at a time. And she is even worse when it comes to naps. I have never been able to put her down drowsy but awake and I am wondering if it has finally caught up to me. I was also bad about letting her sleep in my arms. Is there anything I can do to fix this?

I am so exhausted and stressed that it is impacting my supply, which I know is not helping matters either. I am left feeling like a sleep deprived failure who is caused her baby to get bad sleep habits. I promise I tired to break them, but as a first time mom, I just truthfully don’t know what I am doing. And after reading every Pinterest article and every book I can, I feel even worse about myself.

Edit- I wanted to add that I have given up dairy, citrus, some vegetables, and all forms of tea and coffee hoping that would help.