Energy will pass through our anatomy, which is organic and free flowing throughout the body. Nothing is out of bounds. There will be cloudy breezy sensations and others that feel like you are funneling a large body of energy into a tiny channel. Some things will feel like melting, others are warm or cool as you already mentioned. Floating is definitely a sensation one can get at times. There have been only a few times where these sensations were ever disturbing. Usually there is anxiety around them more than pain.
What hurts more I think is when we begin conditioning the body to hold new positions and we must change our gross matter. The ecstatic buzz, numbness, or tingling I've always experienced, while pronounced much of the time, is rarely painful. Usually it is pleasurable, and acts a field through which I can discern the inner state or shape of my body. The sensations are giving the mind a reading or scan, which plays a great role in my overall process or purification. The mind and body are creating there own language, awareness or concentration facilitates this interface.
So having fear around a sensation can create an obsessive concentration around the area of the body that produces it. I experience massive symptoms in the head and lower back as much of my life experiences were stored in these areas. Concentration draws energy to the place, inducing tons of activity. If it isn't painful, or disturbing to your intuition, I wouldn't worry about it at all.
I remember the first time I felt my heart with my inner perception. It skipped a few beats and beads of sweat instantly ran down my brow and underarms. This was years ago in the beginning stages, where the awareness is investigating its environment/body. The adrenaline felt like a massive wave hitting me, heat seemed to explode from within. Now the energy inside the chest can literally move me around and twist my body into different positions and I find there is nothing to fear, the body is just trying to fulfill its potential by exploring the complete range of its capacity.