Can anxiety and stress cause weird sensations in the heart?

Hello doctor,

I have had weird sensations with my heart occasionally for almost a year now. It feels like my heartbeat goes out of rhythm (slow and hard beats, which are very noticeable). I had issues with my mental health, especially last winter, with mostly anxiety and stress. I still fight daily, but I have gotten a lot better after going to therapy ten times and working on myself, so it rarely affects my everyday life. With that said, whenever I experience these abnormal heartbeats, I often get very anxious and annoyed. I consulted a doctor, and they said it was just due to my anxiety, but I have a hard time believing that since it keeps happening even though my mental health is much better. Having experienced it for so long, I have taken notice of what helps it and what potentially makes it worse or more likely to occur. Alcohol (the day after), stress, and not enough sleep makes it worse, and magnesium supplement and 8 hours of sleep better the condition. So is it likely that I have some heart issue, or is it a reflection of my mental health? Thank you.