You have gotten itchy eyes due to the allergy of eyelash extensions. Rest assured because it is not a very bad condition and you can cure your itchy eyes. Just buy some over-the-counter antihistamines like Claritin and over-the-counter eye drops with antihistamines in them which are helpful to alleviate your itchy eyes. But the above-mentioned over-the-counter eye drops will lose effect after 4 hours. You can have a try of another one, Zaditor. Zaditor is better in that its effect lasts for more than 12 hours and it is even can be taken for kids at the age of 3. You can also go the see an eye doctor for treatment of itchy eyes. The doctor usually will prescribe Allergy or Zyrtec which are not only effective in treating itchy eyes but also helpful to relieve puffy eyes, red eyes and dry eyes.
A lot of people have such similar problems because of the stimulation from the eyelash extensions. It will make your eyes feel itchy and feel bad. You could use the warm compress to cure the itchy eyes. The warm compress will make you feel comfortable at the eyes. You could also use the eyes drops to release the symptom.