Can anxiety cause tachycardia?

Hello doctor,

I have already spoken to my cardiologist, but I have not really gotten much information. They told me I have been experiencing a lot of tachycardia lately but with a normal rhythm. They reassured me that I should be fine, but I did not feel that way. Three months ago, I went into cardiac arrest due to a drug overdose when I accidentally took a pill laced with Fentanyl while trying to get an old prescription for Adderall (Dextroamphetamine and Amphetamine). It took 12 mg of Naloxone to revive me. About six months ago, I had another ER visit after taking what I thought was MDMA at a party with friends. I no longer take drugs. The drug test came back positive for amphetamines, and I had taken around 200 mg of Methamphetamine. I started to go into cardiac arrest again but was thankfully revived. It was a terrifying experience that still haunts me and causes anxiety whenever I notice my heart rate increasing.

Three months ago, my symptoms worsened, and my cardiologist put me on a heart monitor for three weeks. They found a lot of tachycardia but with a normal rhythm. I am not sure if it is just anxiety or if my heart could have an underlying issue. I am only 24, but I feel like these close calls may have taken a toll on my heart. I need some reassurance or an answer as to whether these experiences could have caused long-term damage to my heart at my age. I do not do drugs anymore, though I do vape.

Lately, I have been experiencing chest pains throughout the day, and sometimes I get light-headed and find it hard to think clearly. I will space out and struggle to focus on anything around me. I am concerned that this might be a heart issue or possibly PTSD (post-traumatic stress disorder) from those events. Any information would be greatly appreciated.