CW is difficult for me

I’m using lcwo.net, but I’m having real trouble copying at 20 WPM characters with 5 WPM spacing (effective 10 WPM). I think part of the problem is that I have trouble recovering when I miss a character. I just kind of spaz out. Now, I haven’t been sticking with any schedule let alone daily practice, but I’m determined to get it. I really need an HF receiver and antenna so I can listen to other beginners.