I believe we are due for a refund from the IRS and I want to know if I should have filed early so that I could have gotten the refund earlier. Is that even true? Or are all tax refunds mailed out after the 15th (or 18th for this year)?

My older son filed in February and got his refund within three weeks.

Yes you should have filed early, to get the early refund

The IRS processes returns as they receive them. If you file early and electronically you can get your refund in 2-3 weeks. The longer you wait to file the more of a backlog the IRS has and the time to refund stretches out,

Besides which, if you are owed a refund and don't file early you are essentially loaning the government money interest free.

I filed on February 16th and received my refund on March 4th.

I already mailed them my check, I much prefer not to loan them my money, so I have as little as possible with held so I get more each pay check