I don't think it is too late to apply to osteopathic schools, assuming you have all the other aspects of your application ready to go (e.g., rec letters). But you must decide really soon. Things take time, including sending official transcripts, writing/polishing your personal statement, not to mention getting verified by AACOMAS. Always be aware of each school's deadline, and definitely take that into consideration when choosing where to apply. DO schools tend to get a flood of applications early in the calendar year, when many applicants start sweating bullets at the thought of not getting into medical school. So you are not too late, but definitely don't drag your feet on this - decide soon.