Can you get pregnant 4 days after your period if unsafe sex ??? and how long can sperm stay in your body?

Unlikely.: about 3 days on the sperm BUT fertility rate drops after 24 hrs. Cycles vary so there is some small possibility of an overlap.

Possible: but unlikely. If you have a variable periods with prolonged bleeding lasting more than 6 days, 4 days after your period with sperm lasting about 72 hours it could be possible that pregnancy could occur