Im having a mental breakdown and I don’t know what to do

After being unstoppably depressed for the past couple months, feeling like I hit the deepest pit of despair a few weeks ago and now just festering in that awful feeling for WEEKS relentlessly, I’m unable to sleep, I’m unable to do anything or enjoy anything, I can’t even make it to work on time because it all feels pointless and because I’m exhausted, and when I am at work I can’t concentrate. I’ve been at my desk all day today (after arriving an hour late) and havent done anything other than join the mandatory conference calls I’ve had to get on. Every time someone emails asking me to do something I’ve burst out into tears and had to hide it at my desk.

I’ve also been having so many health problems. I always feel nauseous and have constant relentless stomach aches. I’ve had so much testing done and the doctors say everything is “normal.” So it’s not even like I can explain that I have some sort of illness...... because I haven’t been diagnosed with anything. But I always feel sick. And I was also just assigned to go on 2 business trips literally in a row and starting on a Sunday (like I have to be in one city saturday night to Monday night and in the next city by Tuesday morning) and I have no idea how I’m going to manage that with how shitty I am always feeling. So either I’m going to be suffering or I’m going to have to tell my boss no and both options are beyond stressful and pushing me over the edge.

I don’t know what to do. I called my mom and she said to just say I’m sick and go home and take the rest of the day off because I’m suffering and obviously not being productive here, but I know it’s not going to be any better tomorrow so what’s the point?

Help. I don’t know what to do here. I don’t know how to get better and I can’t live like this.