This number called as soon as I applied for a loan online. They wanted me to send them money before they sent me any money and promised me I'll get a loan for 14000.

Do not send them any money. The scam is they get your money and never send you money.
it is illegal for loan businesses to require a payment upfront.
In the future, other scammers will call you claiming you received money and you now have to repay that money.
Brace yourself.

William is correct!

Advance fee loans are illegal period and in some states, so are the payday loans.   Please be aware the scammers may also claim down the road that you have taken a loan and try to extort money from you that way as well!

http://www.consumer.ftc.gov/articles/0078-advance-fee-loans
http://www.fraud.org/scams/direct-marketing/advance-fee-loans
Payday loans
http://www.paydayloaninfo.org/state-information

http://dfi.wa.gov/consumers/alerts/cashnet-payday.htm
*****
http://www.cashnetusa.com/consumer-notices

http://www.nw3c.org/
http://www.ic3.gov/default.aspx
http://www.fbi.gov/
https://www.ftccomplaintassistant.gov/#&panel1-1
https://consumercomplaints.fcc.gov/hc/en-us
http://www.consumerfinance.gov/complaint/
http://www.fraud.org/
http://www.stopfraud.gov/report.html
Tip off FBI about this extortion attempt by filing form at: stips.fbi.gov/

He said his name was David Clark from LendingExpo.net he recieve or saw I was looking for a loan.He told me that I was approved for 5000.00 and that I can take it out for 36 months my payments would be 164.16 and that they will send me papers in the mail to sign but first I have to send them on a pre paid credit card 164.16 and then my money will be in my account within 3 days.

Read Tamianth's post.  Also consider this.  It will take more than 3 days for you to get the paper work in the mail, review it, sign it, and send it back.  What lender would give you money without having a signed agreement beforehand?