My stutter has been changing recently.

My stutter has been changing recently. Hi, I (21m) have had a stutter since I was really little, and it's always been a repetitive stutter. Certain word sounds like T or S I'd repeat over and over again, and it continued like that for 20 years. Now recently I've noticed I don't do that very much anymore, now it's more before I say a word for example "The" My entire mouth will freeze up and I can't get any sound out for multiple seconds. I have to break my self out of if it by cursing most of the time. Now I was never very well educated on my stutter so I'm just curious what is going on? If it's common? If I should go to a speech therapist etc. Any help is appreciated.