Oh, this bitter taste is so irritating! I asked my gynac at Apollo during my checkup and she said it is because of hormonal shifts like estrogen. The clinical coordinator suggested drinking fresh lemonade or citrus juices, so definitely ask your doctor once to see what they suggest.
I totally understand how frustrating this feels, beta. It makes eating so difficult when everything tastes like metal or bitter. Just hold on, this phase will pass and your sweet baby will make all this struggle worth it.
It is just hormones, ghar pe simple solutions work best. Try chewing some elaichi or saunf after meals to change the mouth taste. Sucking on a small piece of lemon with a little salt did wonders for me during my pregnancy.
I felt so miserable in my first trimester because of this bitter tongue taste, nothing tasted good. I actually cried during dinners because my mother made my fav food and it tasted bad. But it slowly went away by week 14, so hang in there.
I had this too and I kept searching online if it means some vitamin deficiency or bad symptom. Honestly it is just normal pregnancy hormones, but if you feel super dehydrated because of it, please speak to your doc once.