Singer Nicole Scherzinger is reportedly feeling "lost" and struggling to cope with her hectic personal and professional life.

The 36-year-old left her fans worried recently when it was reported she'd tried to jump out of a moving limousine and it's now been claimed her strange behaviour is a result of being too busy to sort out her personal commitments to Lewis Hamilton, reports femalefirst.co.uk.

"Nicole's really feeling the pressure -- she's determined to make her new album and is spending countless hours promoting it.

"At the same time, she has to travel back and forth to see Lewis in Monaco and she's been pushing for a wedding so they can start a family together. She's confided in friends that she felt ill and trapped in the car -- she says she had to get out of the limo and didn't care if it was still moving.

"She's so busy with work, she says she doesn't have time to sort everything out. She feels so lost right now,` the source said.

The former Pussycat Dolls singer, who splits her time between London, Los Angeles and Monaco, is said to be feeling particularly "emotional" because her boyfriend won't set a date for their wedding.

"Nicole's feeling really emotional because Lewis makes her many promises but they still haven't got anywhere with setting a date (for their wedding),` said the source.