That has to be a real concern for the company today: Apple sold 5M units in the smartphone’s opening weekend in the U.S., Australia, Canada, France, Germany, Hong Kong, Japan, Singapore and the UK, it said today. That means demand for iPhone 5 already exceeds the supply. Some people who pre-ordered will have to wait until next month to receive them, Apple says. And production could slow after the phone’s manufacturer, Foxconn Technology Group, shut a factory today in China following fights that Bloomberg says involved as many as 2,000 workers with 40 people hospitalized. A Foxconn spokesman wouldn’t say whether the plant makes iPhone 5 parts. Meanwhile iPhone 5-mania is just beginning: The new smartphone will be offered in 22 additional countries beginning Friday, and will sell in more than 100 countries by year-end. Apple CEO Tim Cook says this morning that although “we have sold out of our initial supply, stores continue to receive iPhone 5 shipments regularly and customers can continue to order online and receive an estimated delivery date. We appreciate everyone’s patience and are working hard to build enough iPhone 5s for everyone.”

How many iPhones will Apple sell? Morgan Stanley analyst Katy Huberty just raised her forecast: She projects sales of 25M units of all iPhone models for the quarter that ends this weekend, up from her previous forecast for 22M. Apple will sell 50M in the last three months of 2012, up from 45M, she adds.  If she’s right, then consumers will have bought more than 136M iPhones in 2012. She expects the sales number to grow to 180M in 2013. But Piper Jaffray’s Gene Munster had to be unimpressed with the weekend sales: He expected the number to exceed 6M and possibly go as high as 10M, website Business Insider says. Apple shares, which crossed $700 last week to hit an all-time high, are down about 2% in mid-day trading.