How To Check For Condom Stuck In Vagina?

Hi, I think I may have a condom stuck inside my vagina as it disappeared after sex (we searched the bed thoroughly). We immediately searched for it but couldn't find it and I have had a dig around since. Is it possible that its so far up I can't reach it and will it come out of its own accord if so? Im concerned it may make me ill (its been 4 days so far). Please give em some advice.
Amy