Heart issue I can't get diagnosed - Is this a problem or paranoia?

I'm 24, assigned female at birth. I identify as a trans male. For almost 12 years now, I've experienced a stab combined with a dull ache in my heart that radiates outward. Almost like someone poking the outer layer of my heart with a sharp, fancy fingernail and then slowly dragging it down over and over. It lasts for around a minute to half an hour and happens completely at random - Laying down, sitting up, eating, drinking, walking, it just hits and I have to clench my teeth and deal with it. It's towards the bottom, somewhere near the pulmonary valve or one of the tubes or something close to those. I've tried multiple times to get a diagnosis for this and have been shoved off to about 6 'specialists' with no definitive answer. 3 told me to lose weight. 1 told me to gain weight. The other 2 said I had anxiety. Of those 6, only 2 checked me with a stethoscope. The other 4 just stared at their clipboard and checked the vitals that were taken. I'm overweight now due to a combination of depression and stress but that only started in roughly 2018. I was always skinny before that. I feel like if this was happening before I gained weight and developed the mental issues I have, it can't be tied to those. But nobody will listen to me. I'm at my wit's end and honestly? I'm scared. You might ask why I've never been to the ER about it - I have. Multiple times. By the time someone actually comes to get my vitals, everything is fine. There were a few times they got some sort of abnormal reading but after waiting an additional 2 hours for a doctor, again, it was gone and they treated me like a needy attention seeker, or some sorta secret drug addict. Now I'm no longer at a point I can afford to pop into the ER and hope someone gets to me in under 5 hours. I also can't keep affording doctors who are just going to jerk me around like a Stretch Armstrong in a game of tug-of-war. Does anyone know what this could possibly be? I've obviously tried looking up my symptoms but the internet just tells me it's cancer or a heart attack. Hasn't killed me yet, but I'd rather it didn't kill me at all. TLDR; I have a pain towards the bottom of my heart that feels like a stab, followed by dull, radiating pain. It lasts for a minute to half an hour. Everyone says I'm just fat or anxious, but I've had this pain since before I gained weight/was diagnosed with anxiety. Please explain to me what could be wrong and what to do like I'm 5, because medical terms fly over my head sometimes. Thank you for your time and care.