Being on all these big medications that suppress your immune system can be very scary and it takes awhile getting used to, not just physically, but emotionally, as well. Keep in mind that the purpose of these medications is to help you lead as normal a life as possible and that includes being around possible sources of infection - your family and friends, the general public, pets, etc., because that's what life is.

Has your doctor told you to be careful because of a suppressed immune system? I would hazard a guess that unless your doctor has specifically told you to actively take precautions in certain situations (wearing a mask or gloves when in public, etc.), you're probably okay to interact normally in the world. However, your version of 'normal' should include washing your hands often, staying away from people who are at the contagious stage (the beginning) of a cold or flu, eating a well-balanced diet, taking a vitamin supplements and exercising (if you can) to make your body as healthy as possible.

Personally, I have had my immune system suppressed by medication for over six years and aside from being a bit more prone to sinus and bladder infections, these medications has actually made me feel healthier than before I took them. I tend to manage the infection risk mostly by frequent handwashing, being very clean in the kitchen, drinking lots of water and telling everyone who are sick that although I love them, I don't want to see them until they're healthy.

That said, I am also not a doctor and am not familiar with the specifics of your situation. Make an appointment to see your doctor or, if you're feeling really nervous and don't want to wait, give her/him a call to discuss your concerns.