First, do nothing. Figure out where you are, which way traffic is coming from and what your options are. Then catch your breath and pick a path to continue that does not interrupt traffic. The nearest corner station can aid you in determining an appropriate time to return to the track surface, so look for them. Once you are going again, proceed directly to pit lane for a brief visit with your driver coach. Whether or not you need to then go change your underwear is completely up to you.