bed bugs

hello there. I think we've got a problem. in my opinion, something bites us at night. and we think it's bed bugs. we have not found them yet but there are definitely bites and marks on the body. help with advice pls, what should we do? should we use some kind of chemical means, heat treatment, or what cleanhomeguide.com/best-steamer-for-bed-bugs/ and how to remove marks from the body? thanks