Yes, razor burn is a bitch and seems to last forever. Since you already have it do not shave that area again until it has went away. The more you shave the more your skin gets used to it. Remember the first time and crawling between the sheets? ahh that feeling was great but it is also because when you first start the skin is super sensitive. For future reference do like everyone else says but I'll add that you need to exfoliate before shaving. Using a conditioner first and then use the shaving cream on top of the conditioner will give a lot of added lubrication for the razor to glide a lot easier and avoid a lot of nicks. In the beginning don't worry about super smooth, a little stubble is a whole lot better than those razor bumps. This is straight out of a Glamour magazine; Use men's shaving cream and razors. The shaving cream for men is a lot better than that made for women because of the difference between facial hair and body hair. Same for the razors. When you are done use a good moisturizer and find a good solid deodorant, Secret is the best and apply that to all the areas that are prone to razor burn such as the bikini line, inner thighs, back of the legs up by the buttocks or anywhere else your prone to get it. Make sure the deodorant though is white and not the clear type. You can also use baby powder with cornstartch but that seems to wear off rather quickly where the deodorant stays a lot longer.
And Just stick with it, the more you shave the more your skin gets used to it and eventually razorburn will be a thing of the past.
