I actually felt lamotrigine to be effective for manic spikes, (as it has been for you) but I did find some difficulty after using it for a few weeks, as the dosage become more.

I'd definitely saw speak to your doctor- I know that you ran out, but I can assure you that good doctors actually praise patients who are intuitive enough to notice these things without being asked 'have you been down?' and you realizing what was happening; you were getting depressed due to meds.
Well done on being conscious about these things.

Chances are your doc will prescribe lithium, a very old, yet very effective mood stabilizer (blood tests for thyroid and kidney function will probably happen first)

An antipsychotic is another possibility, but a mood stabilizer such as lithium or valproate.