Your workspace is on the free trial, which gives you $5 in credit over 30 days. The "2 days left" is the time remaining on your trial, and "$4.4 left" is your remaining credit. Whichever runs out first (time or credit) ends the trial, and your workspace reverts to the Free plan. The unused credit does not carry over. If you want to keep your services running long-term, you can upgrade to the Hobby plan ($5/month with $5 of included usage each billing cycle) from your plans page.

so what if i have left 4$ out of 5$ but the month ends?

Once the 2 days are up, the remaining $4 is lost and your workspace moves to the Free plan. The unused credit does not carry over. If you'd like to keep your services running without interruption, you can upgrade to Hobby which includes $5 of usage each month.