Any variation of sickness is applicable. Some women are sick only in the night, some are sick all day, other women it comes and goes with its own pattern. There is also a difference in whether it's merely a queasy feeling or actual vomiting. Some women will actually have a severe form of morning sickness called hyperemesis gravidarum. This can lead to dehydration and other problems.
Breast tenderness is experienced by many women, both during pregnancy and prior to their periods.
This usually goes away during the second trimester, or it may be experienced as a heighten sensitivity. This can be a good thing for some women. Headaches Headaches are more common in pregnancy due to the changes in hormones. This may be a pregnancy symptom, but it is not necessarily a pregnancy sign. There are many things that could cause this, including stress.