You will be surprised.  Sometimes, when you think you are sober, that is when the worst of things happen to you.   Here are some good ways to find out if you are drink driving:

1.  YOUR HEART RATE is Soaring:  Yes you feel hot and red, and your head starts to get a bit spinny.  At this point, if you can PLEASE do not continue to drink and get home as soon as possible.  Get a friend , get a family member or get a valet and fetch you home.  Start to drink water to get that feeling away and keep sober.
2. ” I AM NOT DRUNK”: Yes you are.  Most drinkers will feel or think that they are sober, when in fact they are spinning and already drunk!  This is the least expected.  But most people who are drunk will tell their friends that they are not and that they are still sober and going on strong.
3. Vomitting: When you get to this stage, stop the car. Or even before getting on to the car, just lay around or even check in a temporary hotel is better than getting on to the roads.  You might be man slaughtering someone instead.  Therefore it is important that you get on the roads with a close friend or at least have someone to keep a look out for you.

It might sound ridiculous that you are not even aware that you are drunk.  But there are really cases like these and you should always be alert and careful.