Lohan spent her first 4 days in rehab detoxing, from alcohol, cocaine, and prescription drugs like Percocet and Vicodin reports Star Magazine.

“She said she felt bad – really bad,�? says the source. But she’s gone through rehab before and she said she’d be OK if she were left alone to lie down in a dark room. She apparently was a veteran who knew the drill and was “used to doing it her own way.�?

She got the “sweats�? during the detox process, but seemed really tough about it. She refused meals, says the source, but wanted water and crackers. This is Lindsay’s second stint in rehab this year, first in January at the Wonderland Center in L.A.

At $48,000 for a 30-day stay, Lindsay gets a room with an ocean view in the 16-person facility. No cell phones or BlackBerrys are allowed, but somehow, say insiders she managed to get her BlackBerry in - and shockingly she’s been asking friends to smuggle sleeping pills in as well!

“She’s in rehab because of her addiction to drugs – everything from cocaine to OxyContin and Ambien – but she’s complaining she can’t sleep,�? says a close friend. “She’s been texting friends 24/7, begging them for pills!�? Insiders also reveal that she’s more concerned about her upcoming 21st birthday bash in Las Vegas on July 2.

Lindsay has given up on meals, but has been loading up on coffee sweetened with about 25 packages of Splenda. A source reveals to Star, “It’s typical for someone coming off cocaine, even alcohol, to load up on sweets. I’ve heard this can happen with almost any patient. Sugar gives you a high.�?