Petra Ecclestone hates being photographed.

The 29-year-old heiress - who has daughter Lavinia, five, and twin sons James and Andrew, three, with ex-husband James Stunt - finds it ''embarrassing'' when she's caught on camera because she doesn't like the attention.

She admitted: ''Every time I get photographed I look miserable. I'm very shy and don't get why they're taking my picture, it's embarrassing.

''If I was Angelina Jolie I would probably be loving it, but people are probably looking and thinking 'Who is she?' ''

Petra previously launched two fashion businesses, including animal skin handbag brand Stark, and though they've both closed with huge losses, she isn't too upset.

She admitted in an interview with the Sunday Times magazine: ''[They were a way of] passing the time.

''I don't see the point in having a business if you're not going to be 100% involved, so I just had to be honest with myself.

''I always wanted to be a stay-at-home mum.''

Despite growing up with huge wealth, Petra insists she had a fairly normal upbringing and wants the same for her kids.

She said: ''I went out with my friends, I didn't have a driver, I lived quite a carefree life.

''I learnt from my mistakes. If you are too shielded or too guarded you want to rebel.''

But Petra admits she's always found it hard to make friends because she's never sure of people's intentions.

She said: ''I always think the worst of someone because I don't want to be disappointed. I expect that they are around for the money or the lifestyle so, when I find out that they are, I don't really get that hurt.''