The official start of the holiday shopping season begins today. But some early-bird shoppers are already done with their holiday gift list.

They shopped Thanksgiving Day, when more and more stores are opening to do business.

At Westshore Plaza in Tampa, shoppers were lined up outside stores like Old Navy before 4 p.m., waiting to take advantage of the big Black Friday sales.

“I have never in my life stood in a line before, so we’re doing it, we’re enjoying the moment,” said Allison Owens at the Westshore Mall in Tampa. “It’ll probably be the only time, but we’re doing it.”

“Embarrased, for my daughter, but I’m doing it for her, I’m in line for her,” said April Mack.

Old Navy was just one of a number of stores opening up Thanksgiving night, although many retailers are holding off on some sales to keep shoppers coming throughout the night.

Many shoppers said they ate their Thanksgiving dinner early so they could take advantage of the sales.

“People are out,” said Jason Burdon, GM Old Navy. “They have an appetite for more than just food today.”

Last year more than dozen major retailers opened at some point on Thanksgiving evening. This year, at least half of them, including Target, Macy's, Staples and J.C. Penney opened earlier in the evening on the holiday.

The National Retail Federation expects holiday sales to grow 4.1 percent to $616.9 billion the highest increase since 2011.

The holiday shopping season is a make-or-break time for many retailers, which can get as much as 20 percent of their annual sales during the time. Already, retailers have resorted to steep discounting to lure shoppers.

As far as getting the best bargain, it may already be too late. Analysis of sales data and store circulars by two research firms says the hottest deals of the season may have been on Thanksgiving.

Meanwhile, retailers have started to see a movement against shopping on Thursday.

The Facebook page Boycott Black Thursday asks retailers to “put employees and families first.”

The page has already gotten more than 119,000 likes.

Information from the Associated Press was used in this report.