This varies from person to person. Some people will feel the fluid moving throughout their body which can feel like a tingling sensation, a flushing sensation, you could feel a temperature change, and/or you may swallow more often.
Afterwards, the region treated should feel lighter and rejuvenated.
Swelling/edema/congestion should lessen.
After this drainage massage expect to urinate either with more frequency or volume as this massage stimulates the lymphatic system which is responsible for fluid volume. You may feel achy as the toxins are leaving your body, but this will be temporary, lasting up to a few hours.
Drinking plenty of water and staying active afterwards will drastically help.
At times, although uncommon, some people can experience what we call the "detox flu". If you are a person who is super sensitive to new things or has a lot of stagnant junk in your body, the detox flu can feel like you are coming down with something. This may also be due to uncovering a bacteria or virus floating around in the body and now we brought it to the lymph nodes for processing. Nevertheless, this should be short lived, only lasting 24 hours or less.