Opinions on cat licking back by his tail and a blood spot

Sammy is around 11 years old.  He is OCD with the compulsive obsessive barbering.  He's had that for years.  His lower belly is very clean. 

Yesterday, I was doing laundry.  When I went in my room to put the sheets back on the bed, there were some blood spots where he was laying.   I found a poop in the litter box of his, but it wasn't a lot.  One time about a week ago, I saw him in the litter box straining to poop, but only one little marble of poop came out.

I'm wondering if he's got some poop all stuck up in there with the hair. 

I'm going to call the vet, but wanted some opinions.   I had a cat with mega colon and I don't want to go down that road again.

Should I start with some sort of hairball remedy/laxative thing?

I have not used it but many people have had good luck with Slippery Elm Bark.  Miralax works well and it works by drawing water into the colon so it doesn't have negative side effects like true laxatives have.  It's more of a preventative though, usually 1/8 to 1/4 of a teaspoon twice a day.  It isn't good to give to a cat that is already plugged up though, it could actually make things worse by increasing volume of stool.

Since you have dealt with megacolon you know some of the things that can be done for constipation.  Increasing fluid intake can help with chronic constipation issues.  Wet food, adding water to wet food, using a water fountain if kitty drinks more with it.  It didn't increase water intake with my two but it does help some kitties.  

I would be inclined to use hairball remedy too to see if that helps.

The vet tech called me and we discussed options.

I'm going to Pet Smart to get the laxatone and try that first for a couple days.  If there is no result, then I will take him to the vet.    The compulsive self barbering may be the cause.  His nether regions are clean as a whistle.  Silly boy.

She felt the blood spot was from the straining.