Second ejaculation

So, while I understand the the possible consequences of unportected sex...I lost my control the other night. My gf and I had got into the "mood" and caution had gone out the window. I had sex with her until a ejaculated the first time...I pulled out and caught the semen in my hand. I knew for sure that I had not come in her...any guy knows what that intense feeling is right as he ejaculates. I then went into the washroom and urinated, washed my penis with soap and water, and then we started to have sex again. Now, I'm fully aware of how my ejaculate feels...but seconds before I was about to pull out again I had a feeling in my penis...it was as if my penis was pumping semen...but much much different. It felt lighter, and it only happened as I was leaving...then I came in my hand again. When I looked in my hand...it looked like the only shot that had come out...so I'm baffled as to what that sensation might have been. Can you feel pre-ejaculate? Would it have been left over fluid from the first time? Fluid that hasn't met with sperm yet? I'm very confused. I've had this feeling before...and nothing has ever come of it. Any help or suggestions are welcome, and I appreciate them all. Thankyou!