There are a variety of similarities between things that happen to the female body when experiencing pregnancy and premenstrual syndrome. Many women feel irritable, have breast tenderness, and are overly emotional. Some females may even have headaches and feel sick to their stomachs.
Throwing up and feeling nauseous are certainly signs. Mood wings are often common along with whether or not your menstrual cycle comes on are tell tell sighs also either way.
PMS symptoms and the symptoms of early pregnancy are very similar. Symptoms include painful, sore breasts, moodiness, nausea, etc. The only way to be sure, take a early pregnancy test.