SOOO exhausted!!

Hi
Its my first pregnancy, about 9-10weeks along I think from working out my own dates cos Ive not had a scan yet. I know its normal to be tired during the first trimester...but Im literally asleep all night, maybe up a couple of times to go to loo if that, but then during the day i feel shattered, i might have a little lie down for a hour but then 3 hours later or something I'm back to feeling tired n needing another nap. Ive had my bloods checked and I'm not anaemic - so is this normal?? Can anyone relate to this?
Ive also been feeling down - i dunno if this is because i feel shattered n have no energy all the time (I'm already on sertraline 100mg for anxiety n depression).
Is all of this I'm experiencing normal, or is it time to be booking an appointment at the GPs n time to worry!?
Thanks Snaily x