Need help quick....

[An882500]

I recently developed a problem with my 88' 2500 with a 700r4 . When i am at a light and take off it shifts form 1st to 2nd but then the RPM's drop and (it sounds as if i were to have a manual trans and shift from like 1st to 3rd kind of sound) then it picks up and then down shifts and then gets going. I havent a clue what is going on with this thing. I checked the tranny fluid and its fine and i just don't know what is up with this truck. I am assuming it is tranny related and hope someone here can shed some light on this for me as i am in a big pinch and i really need my truck for work. Thanks in advance i appreciate it.