My cyst which i think it is, is on my chest not my breast and it got really big red and sore? can it be more than a cyst?

Inclusion Cyst: Inclusion (sebaceous;epidermoid) cysts are very common, arising from a blocked oil gland on the skin. They are prone to infection, at which point they often abruptly increase in size and become red/tender. When infected, they may respond to antibiotics; if not, "i & d" (lancing) is necessary. Once it returns back to baseline, simple excision may be done under local anesthesia.

Infected cyst?: Yes it could be a mass or other lesion. Antibiotics followed by diagnostic excision may be required for a definitive identification.