The injections will cause some redness and welts, like insect bites. These will have gone by the time you take the stockings down.
When you remove the stockings, your legs will probably look bruised and the veins usually look worse before they look better. The veins are usually darker, sometimes with blue, black or brown spots under the skin.
The appearance has usually improved noticeably by days 10 – 14. At 4 – 6 weeks the thread veins should look pretty much as they did before injection and thereafter start improving. The full effect of the injection session is apparent at 12 weeks.