Struggling with Mental Health and Work

I’m having an extremely hard time right now with stress and extreme amounts of mood swings / depression and I haven’t even been working. I start a new job Tuesday and I feel like I’ve fallen apart before I’ll even be able to shine. I’m scared and because of my budget and schedule I couldn’t get a doctors appointment in until over a month from now. I need to get back on some stabilizing medication because I feel like my world is falling apart right now. I don’t know how to keep going without ruining everything because of my mental state and the way I react to things. I don’t even know what to ask for, I don’t know what kind of advice or help I really need or want right now. I just feel so overwhelmed and I wish my parents would be more willing to help me out when I’m emotional cuz they’ve been essentially expressing annoyance every time I’m in a bad state ever since I had to move back in with them.