Genital warts - treatment and transmission!?

I am a 21 year old male and have genital warts! I have used Aldara once and the wart cleared but the itchy feeling is back and im afraid it might have transferred to my (or rectum), How can i know for sure without seeing a dr? im too embarred! I did not have any though, is this possible? Should i use Aldara again... this time on my to? Then lastly i have been sharing a sponge and soap.... is it possible i could give the warts (HPV) to the other users of the sponge and soap? especially a female! This is very embarring so all the help would be very much appreciated and welcome!!!!!