Answer:
I start new then become old. Start clean but be one dirty. I usually start big then become little.
You may enter, but you may not come in. I have space, but no room, I have keys, but open no lock. What am I?
I begin and have no end. Eventually, I will be the ending of all that has begun. What am I?
I have a ring but no fingers. I used to stay still all the time but nowadays I follow you around.
I'm really blue but when you see me I'm red. You don't see me too often. I'm there for you if you're hurt.
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?