Synovial fluid and the result of moving articular edges of the various bones involved in the knee joint.

What @denidowi says. If there is no pain or stiffness, then there is little point in going to the doctor yet.

I have had this problem since I was 13. It started out like that, I went to the doctors he said it was because I was a little overweight. My knee got worse and it started locking, and giving me agonising pain at night time. Back to the doctors, he said it was because I was growing!. My knee just was not getting any better. We changed doctors and he just told me to wear a bandage at night time, when I woke up my ankle was like a balloon. Went to the hospital and they said I was lucky I didn’t have a blood clot. A few week later I had an operation to remove all the dead tissue and fluid in my knee, which you need to have done, it will only get worse. They said if I were older then would replace my Cartilege, but because I was 18, they didn’t. I’m 31 now and I still have problems if I’m hot at night time, I always need it to be cold, otherwise my knee is in so much pain.

@Dibley – Yes; it is a pity they felt they had to operate, because overall, although they do have successes in that area, it certainly does not have one of their best track records.
I have had a bishop, who loved his tennis, who had to have about 6 operations in 18 months, because they had not got it right the first time!
Backs (spines) are an even huger operative failure!!
The general Western medical field just does not understand backs or the meaning of backs sufficiently to indicate a great deal of success at all with them… and many victimous patients believe they would have been better to have left well enough alone in the first place, despite their original painful condition.

It is my experience that, generally, if we as humans start to treat the body right, no alcohol, no tobacky or drugs, no coffee/tea etc and no caffeine, eating mainly raw foods, and exercising at least 5 times per week – both with some slower work and some more challenging “interval” work [Graduated in improvement from humble beginnings], our bodies will cleanse out all the toxics and poisons and begin healing themselves right throughout.

Squishy noise? Mine makes more of the ‘snap-crackle-pop’ variety.

I would definitely get it checked out. Knees are not something to mess around with. It sounds like you have some fluid squishing around in there. I have a friend whose knee would blow up, similar to @Dibley and sometimes the fluid would blow up his whole leg. So I would be careful with this and get it checked out

If there BE such a thing re the current understanding of the knee, the only possibly ‘safe’ undertaking I would allow them to do would be ‘drainage’, that is… should that be absolutely necessary, but not until you have obvious pains and after quite some time and change to your ‘programme’, have still not had success.
Sometimes a time of absolute rest is warranted: it would depend specifically upon your recent past activity history, as to whether it was ‘rest’ that was needed, or whether it was more likely ‘activity’ that was needed along with diet changes.

Okay. Thank you everyone, so first I will try to lose a little weight and see if that helps.

@rowenaz You need to go to the doctors, you need to get the fluid off your knee.

@rowenaz – Weight loss would make quite some difference to you, esp if you used regular exercise and proper diet in conjunction.
If it IS fluid, as Dibley seems certain, it might be worth having that drained also by a doc.
BUT I wouldn’t let any docs recommend anything more than that to be done: many of them will try to persuade you all sorts of drivel procedures.
Your safest bet is as we say, unless there is some Highly unusual disease involved, or you have chipped the patella or something.

I went to see our local physio guy. We call him Magic Mike for a reason. He took measurements of both my knees then had me walk towards him. My left knee veers in a wee bit. We just returned from a trip to China, walking stairs for miles on the Great Wall and Yellow Mountain. The combo of my weight on a knee twisted slightly inward for weeks caused a squishy, disgusting noise each step going upstairs. He has me using a foam roller to pull the tendon? apart from the muscle and then I have an exercise I have to do to help get it back into place. I think before you do draining and surgery and all the other stuff, you should see a good physiotherapist! It sems to be working although I have just started.