Sorry to hear about your problem. Firstly I must tell you that Chlamydia is one the most common and also widespread disease in most of the countries especially the western ones. Also, Chlamydia indeed falls into the std list. It is spread when there is a sexual activity with an already infected person. In your case, I would suggest you that you get your boyfriend tested also. There might be a case where he would have the infection and when you had sex with him then the infection was passed onto you. In case your boyfriend is not infected with Chlamydia then also it can spread if you have lot of sexual contact of your genitals. The fluid might spread the infection. The symptoms of Chlamydia infection is not seen earlier. It might take several weeks before you got the infection to show the actual symptoms. It is very common in females than in men. A person who has had Chlamydia before if indulges himself in sexual activity with another person who has Chlamydia might again get affected with the infection. Hence, it is very important that proper protection is used during sex. Another important thing, I would suggest you to get yourself tested again because in most cases it is seen that a person with Chlamydia might as well have other diseases which fall in the std list. You also get yourself boyfriend tested in order to be sure. Also, you need to get proper medication for the treatment of Chlamydia. I hope you will be fine by the treatment because Chlamydia is curable. Take care.