7yo neutered male behavioral issues

Question
I have a 7 year old neutered male that was adopted from the humane society when he was three months old.
He didn't have any behavioral problems when he was young except for liking an old upholstered chair as a scratching post (we just let him have it because we didn't really care for the chair). He still uses the same chair (but different legs) today.
Summer of last year, we had a crazy flea infestation. I suppose whatever we were using was not enough and the fleas got into my room and onto my bed. I've probably had a hundred fleas bites total over the duration it took to completely rid my room (the only room affected because the cat liked mine best) of the fleas. While we were trying to rid my room of the fleas, we moved him to a separate storage room that was empty for the time being. The room had a medium sized window with a screen and we brought his chair, his litter box, toys...everything. So we would come visit him everyday and decided to use Frontline plus. He doesn't have fleas now and my room and I are flea-free too.
We decided to move him back after three consecutive, consistent applications of Frontline, which was a few months ago. He's been pretty happy for the most part because he gets to see us much more often and we get to play with him more. Oh, and since his return, he seems to like the bed in the other room better than mine now.
But on May 10th, it seemed like everything went wrong. He had pooped in my room in the late morning, urinated on the bed in the other room in the evening and did one of those sudden lunge attacks at my calves later that night (I was walking from the hallway into the living room. I didn't even know he was walking behind me).
For the last couple of months, he hasn't done ANYTHING like the peeing and pooping. He doesn't have a history of lack-of-litter-box-training either. He's always been very good about it.
As of the attacks on my calves, he's had a bit more of a history with that, but once I realized that I had something to do with it, I watched for signs of too much petting and signs of when he wants soft play to become rough play. I can tell by the eyes, ears, tail and posture when he's about to or thinking about pouncing. And that's when I divert his attention. But he's never just lunged at my calves before when we're not playing. This is very new and quite annoying (and painful).
I can't correlate any recent changes in his life or environment to his changes in behavior. The only thing I can think of is the heat wave. We were in mid 70's and then it shot up to mid 90's over the weekend. Though it's cooler once again, now.
Also, he's begun to chew on the broom bristles (it's plastic) and he completely mowed down my little bamboo plant (he chomped off all the leaves). I got some kitty grass for him, but they didn't have any already grown, so I am growing some currently. This is the only behavior that is consistent.

Thanks,
Kini

Answer
Kini,

Have you treated him for tape worm?  Fleas are a part of the tape worm life cycle and, if you have had fleas, you probably have tape worm.  This could cause some discomfort in the back end which may explain some of the problems.  The timing may be about right.  These days, there is a pill to treat tape worm and other kinds of worms as well.  You should have your cat examined by your vet along with a fecal sample.  Even if the tape worm segments do not show up in the stools, I would treat for tape worm anyway.

Also, are there any new cats hanging around the house?  These cats may be causing some undesirable behaviors.  He probably would not like that other cats are hanging around and it could alter his behavior.

Best regards... Norm.