Hi, congratulations on your pregnancy! It's very normal to feel totally wiped out in the first trimester, happened with both of mine (due in a few weeks in DC2). On my days off with DC1 I would just sleep, really struggled to get up for work! Ashamed to say I can't remember when they do the bloods, but I think I had the first lot done at 12 weeks when I went for my scan. Just try to rest when you can, drink lots of water and know that you'll most likely get some energy back in the second trimester!