If I understand your routing correctly, it's MSP-JFK-NRT-SIN-NRT-SEA-ANC-PDX-MSP? At $1430, that's a bit over 6 cents per mile, which personally I would consider a bit high for a pure mileage run. If you're planning to turn it into a mini-vacation, that's another story. But I suggest you're going to be so exhausted arriving in SIN at almost 1 AM and having to be back at the airport for a 6:55 AM return flight that you'll have neither time nor energy to celebrate your birthday.