What's your central conflict? What's the biggest obstacle life presented that took years to overcome or come to terms with? Maybe it's an illness you were diagnosed with at an early age, a relationship wrought with turmoil, a series of career setbacks, a goal you worked for decades to achieve, or any other number of things. Look to your favorite books and movies for more examples of conflicts.
Either way, this jump is disturbing, but the description likely caused you to cringe more than the summary. And doesn't some part of you want to know what happened next? Who came to help? How quickly they reached a doctor? If all had turned out well in the jump, you would not have the same compulsion to read on. If you can't think of any details, write a line of summary and return to fill in the details as you remember them. If you remain relaxed about it, you will remember. If you don't, you don't. Writing an autobiography isn't easy, but it should be enjoyable.
The main body includes the biggest amount of information. It is 80-90% of the whole text. There are no strict requirements, but you should not forget to use a logical sequence and correct wording. You can use the classic five-paragraph structure for your autobiographical essay if your ideas fit it. Anyway, you have to divide your writing into separated paragraphs to increase the readability of your essay. You should also create a logical connection between paragraphs. In this manner, readers will easily follow your thoughts.