No appetite

I am 16 weeks n my hunger suddenly reduces from d last 5-6 days . Today i just had one meal in the morning and its night now and i have no hunger to eat anything ...i feel as if my stomach is already full..like ihad huge hunger in the laast 3 months ..i just had eaten n after 2-3 hours i eat again ...but now it’s totally opposite... even my ol symptoms has gone .... actly i had sex before 10 days lying on my stomach ...so m very worried now dat might my baby gt pressure ...n its al happening due to dat ...m also planning to have appointment with my doc ...plz suggest me sthg ..if anyone experience like dis