Is it normal to have an intense fear of gecko lizards (real ones, not the geico guy)?

Phobia. No not 'normal' but people have phobias to certain things (spiders, bats, clowns, etc.).
CBT. Seek a cognitive-behavioral therapist who specializes in phobias. One method they use is systematic desensitization which slowly and incrementally brings the person closer and closer to the thing they are afraid of in slow, graduated steps that help make the anxiety more tolerable.