tapeworms do come from flea bites. if he didn't give you meds for fleas, then bath her in dawn original dishwashing liquid. it does not prevent fleas but will kill the ones she has and you flea comb them off. i don't know what kind of medicine he gave you for the tapes but few wormers kill them. A really good one Drontal. it is a pill and usually the dose is one half pill. You can open her mouth and push it as far to the back of her mouth as you can. you will feel when you have it back far enough. if you put it in right, she will have to swallow it and not spit it back out. You can get a can of flea treatment spray to spray your couch, carpet and other areas she has been. then you will need to vaccum it up. Here is an article that explainss about tapes and how dogs get them.
http://www.sniksnak.com/doghealth/tapeworms.html