Suspected SVT diagnosis, seeking advice

Hi. I was recently in ER for very elevated heart rate and bp (was swinging around at whim associated with an icy feeling in my chest, 180 was the highest they saw it but I got a few 140-150 spikes even through the meds they pumped in my arm). Couple weeks ago. Only other time I've had anything like it was five years ago- my heart rate randomly took off like a rocket one day, it was beating probably in the 180s and only ever going down to like 90-100 minumum (my normal resting is ~63) and that happened for a couple days straight but no doctors gave me the time of day, probably because I was 17. Eventually went back to normal and just became a source of PTSD. Well now I'm 22 (male) and it's come back for me.

ER doc 1 said it was probably SVT or "inappropriate sinus tachycardia" and that since my heart was in a normal rhythm that it wasn't dangerous, gave me 25mg metoprolol succinate and basically said "this might help a bit but this is your life now". Thanks, sure, okay man. That helped for a couple weeks but now even with the medicine the icy feeling and heart rate spikes are coming back. I'd say it's happening like once or twice a day now? I ended up in the ER again with it yesterday because my BP was at 175/98 and my fiancee yelled at me to go in, ambulance ride drivers said I was having 'small svt runs to 150 self terminating' and some other stuff that's all I got out of it. Said it didn't seem too bad but I didn't feel that consoled. In the ER he essentially said "yeah it sounds rough to be you" and gave me some Ativan for the stress (which, admittedly, has made me feel the most calm I've felt since I wasn't even a teenager yet.)

Currently I'm trying to get with a cardiologist but the referral process takes forever and a day. ER did an echo ekgs blood all that said I'll live but it is still freaking me out. Does the frequency of SVT bouts normally go up like this, will it stop going up? Hell, does this even sound like SVT? Fortunately ever since I got my panic under control when it happens (with the benzos helping just a little bit) the spikes have only been lasting a few seconds. But even coming off the new short ones I get horribly shaky and nauseous for a while.

I have a depressive disorder that's quite severe- I'm looking for someone to be honest with me, let me know what life is going to be like from now on, give me some peace. Because right now I feel like I'm just staring at a clock waiting to die before I get checked by an actual doctor, even though that's totally unreasonable. Just how depressive disorders are, though. Trying to shake off the idea that my life is just out of nowhere ruined forever, which is basically what the ER cardiologist told me.

Edit: I forgot to mention a symptom. This might just be because I've been too scared of more attacks to leave bed much, but just going around the house now brings my heart rate to 110s-120s; used to be 90. Basically, my HR seems to just also be passively higher when active, despite the Metoprolol. Idk if that would even matter, I guess. Sorry, this is my first time baring my heart to strangers online. I just...need some connection, I guess.