The decision is yours as to take a test or not, but if you have not had you're period for 3 months you should really take a test just to be sure, you could always try to find a planned parenthood or something like it on you're area and it's completley confidential and they can help you. Hope you have a support person or someone you really can trust to help you with this situation. All the best.

Wow...Three months. I am only eleven weeks pregnant and although I have been pretty fortunate on having no nausea or morning sickness, no weight gain and I haven't been urinating too frequently, there have been sure signs of pregnancy. This is my first pregnancy and I never realized what a noticeable change it would be. My breasts are extremely sore, and I have been exceptionally tired. My breast seem to be worse when I have been laying down (???) my hair seems to be falling out by the handful and my nails are growing faster than I can clip them. Anyway, have you felt sore bb's or tired or frequent urination, weight gain? I'm sure you've been to all of the websites to read up on early signs and symptoms. Trust your gut, and try not to worry. My husband and I are 28 and married and had no plans on being prego. I actually cried for two days straight when I found out, and now I can not wait - - don't dread it, just trust that god knows what he's doing

There is a good chance you are pregnant. Three months is a long time to go without your period.
My best friend was four months along before she found out she was pregnant. She hadn't had her period, but every single home pregnancy test and even the test at the clinic kept coming up negative. She thought that she was pregnant, but the doctors kept telling her that she wasn't. The only symptoms she had was no period. She didn't get any other symptoms until about the fifth month. But every single woman is different.
Even though you are scared, not taking a test will not make it go away.
Like the first post said, go to a clinic or something like that. They can help you out. You can get a test, exam and if you are pregnant they can explain your options. And if you are not pregnant, then you should consider going on birth control. Good luck.