ADVISE!! Recent premature ejaculation problems

For the past month I've been having issues with cumming to quickly. Prior to this I could go for 15-20 minutes without any problems. I'm stumped as to why this issue has started. Any tips as to why the sudden change? 
Question for the ladies: Would you mind if your guy stops in the middle and goes down on you so that it doesn't happen as quickly or would this ruin the mood for you? I know sex for women is just as much mental as it is physical for you.