Rkeane
Keep a diary, try and establish a pattern and then see if you need to adjust insulin/food.
If you are having hypos in the morning is it after exercise?
Have you changed the type/intensity of the exercise you do, or even the time you exercise?
To test if your levemir is too much, skip your breakfast and then test at lunch time and see if its stayed stable? Maybe the novorapid is a bit too strong, and if so you can get half unit pens (Novo Junior) given you are only taking 1u per day.
You sound quite insulin sensitive, though at 18 months I wouldnt have expected a honeymoon period to be ongoing, or re-starting.
Might give you a better idea once you write it down and establish a pattern, about what times of day you need to 'watch' and you can then take preventative action