I had my own home inspector before buying, does that hurt my case?

It can, in a specific and limited way. California buyers carry a legal duty of reasonably diligent investigation before closing on a purchase, meaning defects that a competent, reasonably thorough professional inspection should have caught and flagged are generally harder to base a non-disclosure claim on, since the law expects buyers to have made a genuine effort to discover discoverable problems themselves.

What having your own inspector does not cover, however, is a defect that was actively and deliberately hidden from any reasonable inspection, common examples include fresh paint deliberately applied over visible water damage, or a structural crack that was cosmetically patched specifically to conceal it before your inspector's visit. The central factual battle in most of these cases ultimately comes down to this exact distinction: what was genuinely discoverable through reasonable diligence versus what was specifically and deliberately concealed to prevent discovery.