How long will my period be I started monday My last period was only three days yet this one has already been 3 and I'm still medium flow I am going to the beach on Saturday and refuse to use tampon?

there is no set time as to how long or when your period will last. If you don't want to use a tampon, you don't have to. I do encourage you to at least try one (start small) so you can see what you like best