Hello and welcome to Ask a doctor service. I have reviewed your query and here is my advice. You have did no protective sexual intercourse and ejaculation was done on chest. You have taken plan B pill after 48 hours. Do not worry chance of pregnancy is less because there is no penetrative sex and plan B pill will protect you against pregnancy. It is up to 60-65% effective on preventing pregnancy. Plan B pill prevent fertilization by inhibition of ovulation. So if there is no fertilization and cause no implantation. Your symptoms of gas could be due to side effect of plan B pill and loss of appetite is due to stress. But to become pregnant penetrative sexual intercourse in fertile period of cycle is required. So I do not think without penetration there is chance of pregnancy. Plan B pill can cause earlier period, delay in period by 1-2 week and excessive bleeding. So do not worry if your period will delay by 1 to 2 weeks. If period will delay by more than 2 week the go for urine pregnancy test and or blood HCG to confirm the pregnancy. If you will be pregnant then you can still terminate intrauterine pregnancy by abortion pill under advise of gynecologist. Avoid stress, take healthy diet, drink plenty of water, do regular exercise. If bloating is not tolerable then take tablet gas x and ginger capsule. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Sagar