My braid accidentally tapped the toilet seat when i was bending over to pick something up should i be concerned for any disease even though its my own toilet i share a house with my sister?

I would be less concerned about a braid that at most touches other distant body surfaces than your fingers/hand that touches your face/mouth several times an hour. (Unless you put your braids in your mouth on occasion) Germs require a favorable environment to survive. This includes moisture & a food source. I doubt your braid would support their needs for long.

What you described is of no concern for your health!. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Get HPV vaccine. Wish you good health! Safe sex: https://www.hopkinsmedicine.org/health/wellness-and-prevention/safer-sex-guidelines