Gosh no, there's loads of ways to stop biting if it does happen, and it's certainly not a certainty. Many babies don't bite at all - ever - and as we're biologically designed to breastfeed for 3-6 years we'd not have done well as a race if babies bit too much
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11 weeks is fantastic - you should be really proud. Here's some things to consider what you've done so far: www.nct.org.uk/sites/default/files/related_documents/Reasons%20to%20be%20Proud%20FINAL%20WITHOUT%20BLEED.pdf
If you do decide to carry on, there's always help and support here for anything you want to discuss :)
If you do choose to change to formula, another thing to consider is that the powder isn't sterile, and when she's no longer getting breastmilk there's no support for her immune system. So, as well as ensuring that the bottles are clean it's also important to pour HOT water (around 70 degrees) onto the formula, then cool to feeding temperature. They say that if you boil the kettle, then leave it for around 20-30 minutes it should be about 70 degrees. Cooler than this and it may not kill any lurking bugs. Hotter and it will destroy some of the vitamins in the powder.
You can make the feeds up, then cool them quickly and keep them in the back of the fridge for up to 24 hours, although ideally it's best to use them straightaway. Not very practical though, when you have a hungry baby, to make it like this when they're ready for a feed. If you do make batches, spilt them down into small feeds so there's no retained hot spot in the centre of a large batch that doesn't cool quickly enough.
As has been mentioned, switching slowly from breast to formula is important - one feed at a time, leave it a few days, then another... Play it by ear and if you feel too full, leave it a few more days before dropping another feed.
Best of luck with whatever you choose :)