Sold my stocks earlier this year. I had to forcibly divest from my 401k last year when I got fired from my previous job, so I had that too. But the rest of my funds were in 1 stock. It went up a lot and I doubled my money, so I sold. Then it kept going up, to the point I would've tripled my money, but I couldn't bear to buy in, especially because the stock was of the company that fired me. 
So I had like 15 grand in my fidelity account and decided to reinvest. I bought a ton of AUR stock (self driving truck company) and it was doing well but has since dumped. Luckily I'm only down less than 10% there. 
But the real fuckup is that I took my 401k money and put half of it into LUCID as it was pumping. I watched a video about how good their tech was and thought it was a no brainier. Saw how low their stock was relative to past highs and thought no way it could go lower. 
Well, it has gone lower. I'm probably down somewhere between 2 and 4 thousand from where I was earlier this year when I was all cash. I'm scared. I don't know whether I should keep holding or I should panic sell. I've been worried about a market crash for years but everything just keeps going up, but now I fear it might finally happen. Should I panic sell now and take my losses, or hold and hope that the self driving company and EV company take off in the near future?
Is there something better I should invest in?