I had an old certificate but just tried to update it with lets encrypt. Everything seemed to go find yesterday but I don't see my ssl certificate as being updated according to ssl lookup. I'm hoping it is not the older software I have installed. Also I'm still running http and not https. Don't need the https features right now other than I want the certificate to show in the browser address bar.
My web server is (include version): Apache/2.4.7; nginx/1.4.6
The operating system my web server runs on is: Ubuntu 14.04 LTS
Without knowing exactly what command you ran to obtain the certificate, and what your domain is, it's hard to give any useful advice.
One basic thing to check is to look in your nginx configuration and check what file ssl_certificate is pointing to. It should point to the certificate you recently obtained.
The certificate doesn't show in the address bar in the current versions of any of the major browsers--the most that would show is a padlock like this: . But it seems kind of odd that you're more concerned with the appearance of security than you are with actual security.