ok /b/ i need help

I thought it would be a good idea to try a new masturbation method by putting a vibrator in my ass while having a wank. Turns out it accidentally fully slipped inside my anus and is still vibrating. the vibration is causing my sphincter to tense so it will not release and i am start to get pains in my lower back. how can i get it out? please help

tl;dr i stuck a vibrator in my ass cant get it out any tips?