Yes, if the STD panel includes test for chlamydia (STD panels differ from lab to lab). It is possible to get false positive or false negative results with the standard tests for Chlamydia. Hence if in doubt, it would be wise to repeat the tests. Else you can opt for specific tests for Chlamydia which include Nucleic acid amplification tests (NAAT, to find the genetic material of Chlamydia), Nucleic acid hybridization tests (DNA probe test, Enzyme-linked immunosorbent assay (ELISA, EIA), Direct fluorescent antibody test (DFA) or chlamydia culture. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.