Will 28 or 32 days be enough days for a std panel test? had unprotected oral and protected anal sex?

Many tests on "comprehensive" STD test panels are unnecessary. After a single exposure, you should have tests of all exposed sites for gonorrhea and chlamydia, i.e. throat, urethra, maybe rectum if you were the receptive partner in anal sex ("bottom") and blood tests for HIV and syphilis. The gon/chl tests are valid any time 3-4 days or more after exposure. The blood tests should be at 6 weeks.

Yes. Syphilis may require a later test