Mold in newly bought house??

Just recently bought a house in may and it took maybe 3 weeks to realize there was a slight mildew odor in one of our closets. So I ripped a small square of sheetrock out and noticed the odor was very strong so I continued to rip the remaining sheetrock out. 2 days after the smell was still there and by chance my neighbor saw me throwing the demolished sheet rock out and ask me what I was doing and I explained to him where it came from. So he informs me that the previous owner had a roof leak (which I made them fix the roof when I bought the house)and had patched a large portion of sheetrock around and above that closet. The seller never disclosed this information (nor the leak from the toilet that nearly flooded the house that he had fixed right before we bought the house). I have sprayed the area with “moldicide” but now im woundering if that’s just the surface and I need to hire a professional. Also if there’s any test out there that I can to make sure I’m not living with black mold in the house. Also the possible liability on the seller and or my inspector I hired. I wouldn’t mind fixing it my self just a little tired of finding things that I need to fix that wasn’t disclosed at the point of sale.