Some early signs of pregnancy are tender breasts, fatigue and mood swings, according to WebMD. Some women may also be disgusted by certain foods, feel lightheaded, or suffer from nausea and vomiting in early pregnancy.
Hormonal changes in early pregnancy are the cause of swollen or tender breasts, notes Mayo Clinic. It is common for the breasts to feel heavy and full. Fatigue in early pregnancy is caused by increased levels of a hormone called progesterone, which causes a sleepy feeling. Nausea and vomiting may occur as soon as three weeks after conception, and some women find that they are much more sensitive to smells than they normally are.