Frustrated

So im only 5 weeks an 1 day. I work somewhere that we have to go up an down long ass stairs. Only my boss knows so far. An other managers that ask me to stock before i leave request heavy things from downstairs. Mind you im a big girl. Like big big girl. I have 2 kids already but so far this pregnancy my betas are slowly rising an i dont wanna do anything to compromise this pregnancy. If i tell the other managers then there gonna tell all the crew an thats something i dont want bc im not in the safe zone yet.. what should i do.. i dont wanna tell anyone yet. But i also dont wanna loose this baby..