I would be more worried about founder. Not sure what the popping is, but no if its constantly popping when she walks that is not normal. If her front feet are warmer than the front that is a common symptom of founder. Founder is not something you want to wait to treat. The sooner you treat founder (first stages are actually called laminitis), the better chance they have of pulling through it. It will not hurt to cold hose or ice her feet a few times a day. If at any moment in time she begins to rock her weight backwards and get in a position that looks like a dog stretching that is a position called the 'rocking horse stance' and is a sign that they are taking off the weight from their front feet. If it were my pony I would have a vet come out and do a hoof tester and take some radiographs to make sure there is no rotation of the coffin bone. Also radiographs will show if you are in the earlier stages where the laminae (which connects the bone to the hoof wall) are just inflammed, if this is the case usually taking them of grass and grain, and putting them on some anti-inflammatories and cold hosing will do the trick. Always, always, always check with your vet, I can't tell you how many people I have known that have lost ponies to founder! My welsh pony is a rescue from a founder case, and he started the same way apparantly and within 48 hours had foundered so badly that he couldnt stand anymore, the owner was going to put him d own, .luckily the equine clinic that I worked for did the surgery for me at no cost so now a year later he is completely sound and even competing on the A circuit!