New to mixing/mastering, my mixes are thin

Sorry if this is a basic question but:

I mixed a song and got it sounding decent but the levels were all huge and it was clipping. I learned about gain staging and went through the whole process of it, and then remixed my song. It sounds ok but somehow sounds very weak and thin. The original mix sounded fat and full. When I compared the wave form with a song by a professional artist, it looked like the image here (my song on the bottom).
I couldn’t get my levels up higher without it going over 0 and clipping. But it just sounds quiet and feeble. I suspect I am missing something obvious here. Any recommendations?

1.This is the german forum
2.If that is the mix with your meters (btw: which meters? ) not going over 0 dB FS, then you are probably not understanding your metering corrextly.
3.A thin sounding mix does not in the first place have to do with volume levels.
4.Depending on the signal flow of your mix, of course lowering the different channel levels can have drastic effect to your mix.