The shadow on the orange looks too dark
Or maybe you've done over the back of it with the purple ?
To get more subtle shadows try using a red to shade it or if you mix it and don't think it's dark enough try just putting a spot of brown or black in it and I mean a tiny spot, you can always add more but too much and you'll kill the original colour. That would shade better I think, that's just my opinion though.
If it is the purple bleeding through, next time back the orange with white before you do the purple, it should keep it's vibrancy then.
Anyway... I don't know how you intended the design to look so I'll get me coat now.