You may have developed a Type IV hypersensitivity
(delayed sensitivity) to chemicals often found in cheap lipsticks but also in expensive ones and patch tests (through a Dermatologist
) will help in determining which chemicals you have become allergic to.
Patch tests involve a series of chemicals (in tiny amounts) applied to the back and secured with a tape and remains in contact with skin for 48-72 hrs and then read by a skin specialist. Any redness
or blisters around the chemical confirms the allergy
Hope this was helpful.