Hi overwhelmed,
I'm so sorry for the loss of your mum. I can really understand how finding out you're pregnant since she passed must be very difficult. You naturally want to share moments like that with her.
I'm sure there will be some mums who will reply to your post who hopefully can offer suggestions on helping with sleep whilst pregnant.
I'm not a mum but can sympathise with the lack of sleep, it makes everything a million times harder doesn't it! I too have dream after dream about my family members that have passed away and then when you wake up its like finding out all over again.
Have you asked your doctor about the sleeping, if not maybe they could suggest something. I'm currently trying all the natural sleep aids like lavender oil, prebiotics, valerian tablets (although I know for you these may not be an option whilst being pregnant).
Sorry I couldn't be of any help but just thought I'd reply so you know you're not alone
xx