Transitional Effects All the Same

I am referring to the Video Transitions Dissolve.  When I tried the Additive, Cross, and Film Dissolve, they looked all the same to me.

I am using 1 or 2 transitional effects and not too much more.

Also, I am new to Premiere trying the trial right now to see if I should get it other than my old Video editing software.

There are hundreds upon hundreds of transition options out there, just search for "Adobe Premiere Transitions" and you will be flooded with free and pay options.  Using them can sometimes be a bit complex though, so it isn't always just apply it to the end of a clip and done.

What are you trying to do? The only time I have issues with transitions is if I have too much going on in a single clip.  Premiere doesn't always like when you pile on effects to a clip.  Say if I apply Reverse speed, then Speed Ramping with Optical Flow to a clip.  I can render it out and be happy, then I may apply a random transition to it and the whole clip or just the transition can get screwy.  So we may need more information. 

And just to take a stab at a fix, are you fairly new to Premiere? If so have you considered just uninstalling and doing a fresh install?