Is it bright yellow
During pregnancy, the cervix becomes closed and blue or purple in color. Also the cervical mucus tends increase due to hormonal changes.
No it does not have to change colour if you are pregnant.
You should never fast or trying to loose weight during the pregnancy.
Yes, chicken is good during early pregnancy.
Changes in hormone levels during your pregnancy will change the appearance of your aureolas and nipples throughout pregnancy and afterwords as well. They can change in shape and color at anytime.
Nausea during pregnancy is caused by changes in the hormone levels in the body during the early stages of pregnancy. It usually happens early on in the pregnancy.
This early you can sleep in any position you want.
Bleeding during pregnancy is not "normal" but some light spotting is reported by about 50% of women in early pregnancy.
You should contact your doctor for any bleeding during a pregnancy.
In my experience, my belly button did not feel different during early pregnancy.