LINDSAY LOHAN was arrested early yesterday morning at a nightclub . . . (--Where else, right?) . . . for allegedly punching another woman in the face.  And it may have had something to do with a free psychic reading.

There are about a million different versions of exactly what happened.  We'll break it down for you as simply as we can.

It was 4:00 A.M. at a New York City club called Avenue, when Lindsay decided to punch a 28-year-old woman named Tiffany Eve Mitchell in the face. 

Sources say they were sitting at adjacent booths, and at one point, Lindsay told the woman to, quote, "give me my space."  Shortly after that, she punched her.

Police were called, and by the time they got there, Lindsay had already tried to flee.

TMZ Has videos of the arrest...She was in the passenger seat of a car outside the bar, but cops intercepted her and arrested her right there.  She was booked for 3rd degree misdemeanor assault and released at around 8:00 A.M.

(You'll also notice that Lindsay kicks her assistant out of the car as she gets in.  He later Tweeted, quote, "After bailing you out last night I HOPE and PRAY you get the help you so desperately need.  We are ALL rooting for you.")

The other thing we know for sure is that earlier in the night, Lindsay had attended the JUSTIN BIEBER concert at Madison Square Garden.  The boy band THE WANTED was his opening act.

From there, the details are all over the place . . . but The Wanted may have played a part in the chaos.

A source says Lindsay totally wanted to get her hooks into a member of the group . . . one MAX GEORGE.  And he did show up at the Avenue to party with Lindsay. 

But she was getting so drunk and annoying that he turned his attention to Tiffany.  And that's why Lindsay slugged her.  Max, meanwhile, ended up leaving with a THIRD chick.

Max did Tweet about this chaos, but all he said was, quote, "eventful night!!"

But Tiffany might not have been competing with Lindsay for Max's affection, because her HUSBAND was at the club with her.  And he later told the press, quote, "Lindsay Lohan got drunk and went crazy . . . [and] hit my wife."

Also, Tiffany herself says this started over an offer for a FREE PSYCHIC READING.  Tiffany is a psychic, you see.  And she says she had a premonition about Lindsay, so she offered to give her a free reading.

Lindsay turned her down and told her, quote, "Give me my space."

At this point, according to a source, a friend of Tiffany's started hurling insults at Lindsay . . . calling her …well, not a nice name…rhymes with lore… and saying her movie "Liz & Dick" sucked.  And that led to the punch.

And finally, according to some reports, it all started when Tiffany bumped into Lindsay while she was trying to avoid a fight that broke out in the club earlier in the night.  Apparently, Lindsay stewed over that for a while before deciding to sock her.

The big question is, of course, whether Lindsay was drunk.  Some sources say no . . . some say yes . . . and one says she was downing vodka and SNORTING COCAINE.

That source claims the whole thing started when Tiffany asked to take a picture with Lindsay, and Lindsay rudely refused.  The woman just walked away, but for some reason, Lindsay wouldn't let it go.

The source says, quote, "She totally sucker-punched that girl in the face out of nowhere! Nobody saw it coming.  Lindsay went wild. She was kicking and screaming, cursing at the girl and then spit at her."

Of course, Lindsay's attorney says she was NOT under the influence of drugs or alcohol . . . and added, quote, "From my initial investigation, I am completely confident that this case will be concluded favorably and that Lindsay will be totally exonerated."

(Here's a picture of Lindsay's victim . . . who says she suffered some bruising and swelling as a result of the sucker punch.)  (People)