Is having difficulty sleeping a common side effect of losing weight and getting fitter?

I’m losing weight at the moment (intentionally) and am exercising4–5 times a week aerobically as well as walking a lot too.

Since I’ve started doing this 6 weeks ago I’m having a lot of trouble getting to sleep and staying asleep…ye I still feel tired…physically and sleepily (I mean like – eyes tired..)

Is this common? and what should I do about it?

And for those who don’t know – I have a 2 and half year old who gets me up at 6.30am every day so no chance of lie ins EVER!

Oh…and I try to go to bed between 10 and 11pm…but if I go any later the tiredness just gets ridiculous!

Suggestions, Criticisms, Encouragements all welcome!