Was This a Nervous Break Down?

 My son was born June 17th. Ever since that day he has been the sunshine of my days. All i do i do for him and i do it alone. My boyfriend is not cut out to be daddy. He's only 17 and he's no ready to give up fun yet so that leaves me to do everything. For the past 2 months I've been doing the best job as a mom that a 17 year old can do. Sometimes its hard but i feel like its all worth it when i see my little baby smile. His happiness is everything to me. But today i snapped. i didn't even know anything was building up until i exploded. I was walking home from the park and i just couldn't go anymore. My body stopped working i shut down on the street corner. It was hot, the baby was crying, i felt overwhelmed and i just couldn't do it anymore. I fell to the ground and cried i was shaking and breathing erratically. In my brain i kept trying to snap myself out of it but i couldn't. i felt so crazy i didn't know what to do. and all i could think was i have to stop get up get home get up get home stop crying stop it!! but i couldn't. Now i look back and feel like a nut job. What is wrong with me?