Hi,
Welcome to ehealthforum,
The symptoms that you describe could be few of the early symptoms suggestive of pregnancy, especially if you have been sexually active without protection after your last normal periods. If pregnancy is suspected, you should consider visiting your doctor/gynecologist for thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). If pregnancy gets ruled out, further evaluation would be needed to look for underlying cause for your absent periods. Treatment as indicated (based on examination findings and investigations results) would be started to help you get your periods and regulate them.
Take care.