Invested everything in $QQQ in Nov 2021. Down 30%.

I had a lump sum saved for home purchase. I live in a HCOL area and I am not quite there yet.

I read online that lump sum investment in index funds beats DCA in the long run.

So, I went all in on $QQQ. When it went down 10% by January, I added a few more pay checks into it.

Now I am wondering if this was a mistake. I have postponed home purchase due to rising rates but can't stop feeling that I made a mistake.