Hi Maria, Welcome to Health Care magic. I have gone through your query and i would like to answer you step by step. Coming to first question- Yes, a vibrator can damage hymn due to direct injury. For that matter any foreign matter and even fingers can damage hymen while masturbating. Even the vaginal walls can get damaged due to the frictional force and the heat generated by the vibrator. Coming to your next question about pain abdomen- The pain in lower abdomen can be due to a GIT cause or a genital infection or an UTI or simply a muscle strain. As you have not mentioned anything about abnormal vaginal discharge or fever , the chances of you having genital infection is highly unlikely. As you have not complained anything about burning sensation while passing urine, the possibility of an UTI can be ruled out. Now we are left with GI causes and muscle strain. In case if you have any abnormal bowel movements like passing hard stools or have constipation, the pain could be due to a GI cause. As far as my guess goes it could just be a muscle strain. Coming to your final question- The chances of you getting an STD is highly unlikely as you have mentioned that none of your family members had a history of STD. But there is a chance of you getting infected due to the bacteria and fungi present in the dirt. Final Verdict- Just Stop worrying. You are highly unlikely to be having an infection. In case if you have any fever or abnormal vaginal discharge see a gynaec and get treated accordingly. Play safe and be careful while using such instruments. Take care