Letrozole and scattered brain

I transitioned from Tamoxifin to letrozole two weeks ago (along with monthly lupron shots three months ago). This week I have:

- Packed for a trip, without my phone charger, my kindle, or my hairbrush

- Almost missed the turn for the dentist

- Almost missed my exit on the highway

- Picked up my phone to respond to a text, only to fall into another app black hole.

Anyone else experienced being scattered on letrozole? Trying to figure out if it is the drug or some other root cause (not enough sleep, because it does seem to be driving insomnia as well :-))