Writing music when happy?

Taxi on my way out to Heathrow. I wrote a hell of a lot of songs in London. The Astronaut, Talk, All I Do, One Day with Sunshine One With Rain and many more. And I have never been in worse life situations than my time in London. It's hard to break trends, I've been really grumpy since I got here, just trying to make time pass so I could go home. That has something to do with why I wrote all those songs here. I should have brought a guitar!

I am learning to write music in a happier mood. I have to. This is of course a good thing, but sometimes I really long back to the days when the lyrics just burst out of my heart whenever I wrote songs. Now I sometimes find it hard to actually get the songs done. I start off and find a great melody, a riff, I write a verse. Then I get the feeling it's not unique enough, that it doesn't really matter. And I stop. The only songs I have finished writing the last year is basically Believe In You, Waiting For Your Call, and the Intro for the album. Luckily those are some of my best songs.

I really feel I'm on the verge of nailing a couple of new songs. Now after some studio sessions I know more what kind of songs I want to write right now.