Demotion Shield

So I am in d4 with 0lp and i just lost 3 games or 2 in a row idk and idc tho, but I never knew there was actually a "demotion shield" which allows me to not get demoted, however under my rank it says "demotion shield is expiring" and the sign is yellow, I wanted to ask if it actually says when it completely expires and so the next lost will grant a demotion, or it does simply mean that im always ijn risk? Does the sign turns red or something? By the way im also searching for a duo who can play top or jngl, dm me if you want to duo up