As a faetus my birth mother was on antipsycotic drugs and injections. would it have damaged me or increased my chances of getting scitzophrenia?

Unlikely: These things are har to study, but its unlikely that prenatal antipsychotics increase risk of schizophrenia.

Antipsychotic meds: Most recent studies have shown no increase in fetal malformations with high or medium potency antipsychotics like haldol, (haloperidol) stelazine, and trilafon -- but risks are a bit higher with low potency ones like thorazine. This isn't the same as risk for schizophrenia -- you may have some inherited genetic risk whether your mother took meds or not. Many factors affect whether someone manifests this, tho'.