Yea your overly paranoid sweety. I mean unless you were ALREADY pregnant. But it can take up to 5 days for the sperm to fertilize the egg and still another few days for it to implant into the uterine wall. When did you last have your period? And what are your 'symptoms' they could be paranoia, ovulation, or an upcoming period. Well it would be anything!
Pregnancy doesn't happen overnight. What you felt is something else or in your head. It's impossible to feel symptoms after one day. You COULD be pregnant, but you won't find out for at least two weeks since your last sexual encounter.