I've been having issues sleeping

Ten days ago, I was crushed by a friend who said my artwork was bad. Idk why, but it hit me really hard. So I fell into a depression and slept for around 12 hours. The next day, while trying to fall asleep, I saw a YouTube video about lethal insomnia. My medical paranoia skyrocketed for no reason just because I couldn't sleep. I eventually called my doctor to basically tell me I was just being paranoid and they did so. But I've been having difficulty sleeping since then. I'll sleep between 2 and 4 hours and wake up. While trying to go to sleep, it's like my mind is racing but my body is tired. I haven't had what I'd call a good sleep since those 12 hours I slept.

I want to say it's stress? A lot has happened over the past ten days, including me putting stress on myself by deciding to improve my artwork, among other things. Any advice?