Ok....need some advice. Suppossed to be doing a 24hr urinalisis....?

you know where you collect all of your urine over a 24 hr span & turn it in for tests & evaluation to your Dr. Wellll, my stupid self accidentally forgot to pee in the pee-catcher & went in the toilet ( you know like a normal person LOL) Sooo...I dumped out the urine & figured Id start over. Now my BF is stressing telling me I cant use the same container, that it will be contaminated & will err my results. He says the very small amounts of urine in there will turn in to bacteria. I told him Id just wash it out w HOT water but he says then the urine will be contaminated by chemicals in our water & my results will still be tainted. BUT in the instructions given to me with the urince container say if I run out of room in the container that I can use an empty milk container or something like that as long as all the urine is kept COLD & that it is brought to the lab the same day i finish the test. So if I start on Sun AM & take the urine to the lab on Mon...I should be fine? Do I need to be worried about the VERY small amounts of tap water that may remain in the collection jug?