What constitutes "full time"?

(It was, by the way, a very good adventure. Husbink particularly took some amazing pictures of lochs with fog and wisps of cloud...I shall do them justice at another date...but for now...)
I believe in part time work, quite strenously! As well you know (if you know me), this is nothing to do with being lazy, it is to do with being healthy and happy and seeing Husbink and looking after him and all that sort of thing.
However.
Over the past few weeks, I've been picking up more and more work. It seems that rather a few students got their GCSE mock results over the past month and there has been panic in the ranks and a need for tuition has arisen! So I refuse some and accept some. I now have five hours of tutorials a week, plus all the travelling that they bring. I might be picking up another student next week too but all seems to have gone quiet on that front so I am probably not.
Anyway. I still technically only work 25 hours a week, plus the travel. That makes 30 hours at the absolute maximum. Most full time work is at least 37 hours a week but I am doing enough - more than enough actually, I feel my time being stolen. The house is suffering a little. A couple of my outside interests are suffering. I am quite content though and with the nature of my students, I will lose them all in a few months time once exams are over and can then start again deciding how many to take on and where to "put" them.
But my point is, I keep thinking "I'm working full time now" - which I'm not, officially, but to me I am.
I know lots of you work proper full time or more than full time...is it because you love your jobs? Or that we value our time differently? Or that I'm just quite lucky to be able to be so picky? Or a little of all of the above?
In other news, I have new glasses. Because my eye sight has improved. I'm less short sighted all of a sudden and so reading and writing and knitting (three major uses of my time) were becoming very painful.
My glasses are mostly black and a little bit orange. Not what I was expecting but I rather loved them so...(oh, and they are a lot more subtle than that sounds but I did enjoy telling Husbink over the phone that they were BLACK and ORANGE. He was afraid...)