Should I wait or not.?

I sent about 15 resumes on Monday and so far, I only got one call back. I had my interview with them yesterday and I think it went well. They told me they'll call me back next week. As for the other companies, should I wait a few more days for them to call me or should I just accept the job offer from the company that interviewed me. How long does it usually take for companies to call their applicants for interviews?