Working while pregnant

Hello mga mommies, asking for advise. Full time elementary teacher po ako. 8 weeks preggy, expecting twins.First pregnancy ko po. Medyo worried ako sa health ko since sobrang stressful ng pagiging teacher. Madalas sumasakit puson ko kakasaway sa mga makukulit na bata. Should I resign po ba? D ko kasi alam gagawin ko, iniisip ko naman may contract ako until end of school year which is on march.. Asking for advice. Thank you very much!