I just noticed i have small group of reddish bumps on my left big toe. they look almost like small unopened sores. what is this?

See below: Without looking at it or having a photo, it is likely either a fungal infection or warts. You should see your doctor (primary doctor is sufficient) to have it checked out.

Red bumps: Without seeing them it can be very hard to offer an opinion. It can be dermatitis , athlete's foot , infection, etc. Seek the help of a podiatrist. Good luck.

Hard : To diagnose without seeing it but could be allergic reaction, fungus too many possibilities . See dermatologist or podiatrist.