Crying for no reason

It's been three weeks since my miscarriage and today at work I had a rude customer on the phone. When I hung up I started crying for no reason. I've dealt with customers like this many times and have never cried. I hate this feeling of not being able to control my emotions and the crying can be so random! Anyone else have or had problems like this? When does it stop? I feel like nothing will be normal again.