Hi jitteryme:
I'll be 46 next week and it sounds like we are sharing similar experiences, however I've had anxiety problems for ten years (maybe I've been in perimenopause for ten years??). I also suffer from menstrual migraines, terrible menstrual cramps and, lately, irregular periods. I too hope that this is the worst, but from what I've read about menopause, it's a whole other set of uncomfortable/painful symptoms. I've had a few hot flashes in the last couple of months, but they weren't that bad...I actually laughed through one of them because I couldn't believe how hot I was all of a sudden.
Anyway, here are my suggestions for you. For your palpitations, you can ask your doctor for a beta-blocker. I took Atenolol and it worked wonders, and even helped keep my anxiety at a manageable level (I had no panic attacks when on it). I have breast cysts also, even a couple of biopsies, but they are benign. They mostly hurt around my period, so I take a diuretic and Aleve to help with the bloated feeling. I take an over-the-counter diuretic, but you can get better ones from your doctor. They make you urinate more, but overall you feel better without the bloat. My experiences with antidepressants were horrible, like yours, so I don't want to go that route again. My gynecologist has suggested taking Sarafem for PMS/PMDD, because I get really cranky before my period. It is the same drug as Prozac, but you only take it for a few days out of the month. It has the potential to have the same side effects as the Paxil-from-hell I took for a month. I have chosen not to take it, but it is an option. If I get pain with muscle tension from stress, I sometimes take a muscle relaxer called Soma, usually only at bedtime. For anxiety, I take Xanax, but usually only when I think I'm going to have a panic attack or sometimes when I have PMS to help keep me from screaming at my family. They are so understanding...I don't deserve them, but they know it's not my fault and I go back to being normal after my period. I tried taking a low-dose birth control pill to regulate my period/mood/cramp/headaches/etc., actually two different kinds, but the side-effects were horrible (more migraines and I gained weight, to mention a few). I take other things for my migraines, but you didn't mention that so I won't go into that.
It seems like your biggest problem right now is the anxiety. I can't say if it will get worse or not, everyone is different. My anxiety is always higher around my period. If there are really stressful events (like the holidays, or my sister's divorce, for example) my anxiety skyrockets and I need to take more Xanax to get me through. I try to eliminate stress whenever I can (shopping online instead of the mall, for example), solve whatever problem keeps me up at night and that helps a lot. So, for me, anxiety is intermittent or cyclical.
Sorry for the long post. I hope you can find some relief. The people here are a great support and have wonderful suggestions, so you've come to the right place.
Best wishes

-SRMom