I'm buying a 1 way to enter usa because its cheaper and a 1 way to return home 4 weeks later. The return tickets are 200 dollars more so I bought it one way each way.

I think you are OK as long as you have the actual return ticket in hand when you are at the airport, but I would ask. I knew someone who was locked in a room and sent home for only having a one way ticket (and not enough money to stay in the country for very long).

I have never in my life known of a one way ticket that didn't cost a LOT more than a round trip ticket, so this is an odd story.

Using priceline name your price for 100 and return home oneway is 280 that's 380 vs my return ticket of 580. By the way I'm flying home from different airport

Happens here all the time ( of course I am in China. We bought one way tickets down, into the city next to Hong Kong and flying out from Hong Kong becaue that was much cheaper.