Congratulations sa baby mo! Hindi siya makakasama sa baby kung magtrabaho ka, lalo na kung kaya mo pang mag-rest at kumain ng maayos, ang stress at pagod mo mismo ang mas importante i-manage para sa iyong health at milk supply kung nagbe-breastfeed ka. A few of us mums went back to work around 2-3 months and ang babies namin ay naging okay naman, but night shift plus stress environment is really tough especially ngayon pa lang galing ka ng pregnancy, maybe try to talk sa boss mo about day shift options or lighter load muna while you're adjusting? Best to check in with your OB though dahil exhaustion at palpitations agad agad after pregnancy can sometimes be something worth looking into, just to rule things out and make sure you're really ready to jump back in full force.