2003 Lesabre clicking transmission noise

My Lesabre has 65k miles and I recently noticed that the transmission would slip when accelerating in 1st gear and reverse. Not all of the time but at least 10% of the time. Also the filter was recently replaced.
Just today there is a clicking sound when I take off and also in reverse. Once it shifts into 2nd the sound is gone.
Any idea if this is an extreme problem before I take it in. Thanks in advance!

Don't worry about responding. I drove it off a cliff. No more clicking sound now baby! woohoo!