恶心 (ě xin) is the common word for feeling nauseous or disgusted, and can also be used as a verb meaning to deliberately gross out or embarrass someone. 过不去 (guò bu qù) specifically means to make things difficult for someone or embarrass them, without the disgust sense. 反感 (fǎn gǎn) is a noun/adjective for a feeling of disgust or aversion, not the act of disgusting.