Weird talking?

Alright, so... DD1 has some major, known and noted speech delays. She's 3
and it's hard to miss her speech problems as 99% of people find her VERY
difficult to understand when she's talking.

Now, though, DD2 has come up with a weird one. DD2 does not have any speech
problems that I know of. I find DD1 and DD2 speak at about the same level,
and speak at what would be expected at DD2's age (she's 2)
Just today, though, DD2 was talking kind of weird... She was saying
something (can't remember what, off hand, but this happens, it seems,
regardless of what she's saying, and if she says something while I'm typing
and does the weird talking thing again, I'll take note of it)
So while she's talking, she kind of goes, "t-t-t-t-t" after saying some
words and it doesn't matter what she's saying, usually (context, I mean).
Right now she just said, "I don't know, I sit t-t-t-t Mommy" and again, "Up
p-p-p-p Mommy" or, "Gone rabbit t-t Mommy" "I find it t-t-t-t" "Feet t-t-t
on" "Take k-k-k-k. Welcome Mommy"
Kinda if that makes ANY sense at all... It's almost like a stutter, but I
JUST noticed it this morning and it kind of caught me off guard a little
because she has NEVER done this before.
One, two, three, four, six t-t-t, seven, eight t-t-t, nine, ten - she just
said to me (she ALWAYS misses 5 when counting) but kind of did the t-t-t
stutter thing after six (she says more like "sits" for 6) and again after
she said eight.
Should I be concerned?? It's almost like she doesn't know she's doing it or
something. I don't know if she hears it.
She just said, "More s-s-s-s-s-s bubbles Amie" and I'm not sure where that
came from with the s-s-s part...
But anyways... I am concerned and wondering because she's NEVER done this
before and I have definitely noticed it happen over and over and over today
only...