You may not ever pass another 18 inch tapeworm. Most species of tapeworm are only 1/2 inch long are are grayish white. When a person hosts a large tapeworm like you did, there is usually just one. Their bodies are segments that are reproductive organs that are making thousands of eggs per day. Most all of these eggs are passed in the stool. You may very well be passing small tapeworms and/or a variety of other parasites at this time. It must be a hard thing to deal with - knowing that a disgusting "monster" of that size was actually living inside of you. You are doing the right thing in keeping up with a parasite cleansing schedule.
The very best herb for tapeworm removal is Balck Walnut - the tapeworm absorbs the tannin (organic iodine) juglandin, juglone, and juglandic acids which is "poison" to them. It also oxgenates the blood, which helps to kill parasites. Wormwood is second to black walnut for tapeworms because the tapeworm will absorb the thujone, isothujone, and santonin which will poison them too. The sesquiterpene lactones in wormwood will weaken the membranes of parasites (it acts like peroxide) and will kill them. ONE MORE THING about wormwood - it is a natural narcotic analgesic that delivers pain relief - it will help your spine and nerve problems too! My grandmother used it for severe pain relief for only short periods of time (two weeks at the most). Keep me posted on how you are doing.