There is no such thing as being too healthy, too happy, too rich, or having too much love!
If you and your mate are madly in love with each other that can never be a bad thing. However if one person has a different level of love or would rather express their love in a different way than you then there may be some issues.
Generally speaking when someone wonders if they love someone "too much" odds are (they don't love themself enough).
Most likely they sense an "inequity" in the emotional investment within the relationship.I recently wrote a hub on this very subject.