Should I be worried about my laser tattoo blister that has popped and is now peeling? (photo)

Blisters should be managed by your treating doctor on the next day after laser tattoo removal treatment when these usually appear in order to avoid their rupture and consecutive peeling. 
But now you are already at the stage of peeling after your laser tattoo removal session. So, you'd need to immediately see your treating doctor for the following: 
The treated area needs to be disinfected, e.g. by the application of betadine dermal solution in sterile conditions. Then the affected area should be covered and protected by a sterile dressing medicated with a cream or ointment of neomycin (anti-bacterial agent) and triamcinolone acetonide (relieves itching, inflammation and redness). This helps to stop the peeling, heal any inflammatory and/or infectious process in the treated area. Dressings should be changed daily. Healing may take a few days till one week. 
The appearance of blisters after laser tattoo removal is a normal though not so frequent phenomenon. This happens especially in hypersensitive or allergic skins and at times may be due to friction with clothes being worn over the treated area. Hope this helps.
 

From your photo it would appear that the reaction that you had is expected.  You do not say when the procedure was performed but, it is not unusual to have peeling and blistering for several days after the treatment.  Our protocol is to use strataderm or bacitracin with a light dressing to keep the area clean.  Watch for signs of infection such as increased pain, pus , redness, fever or chills.  You should call your provider with your concerns. Your provider can best advise you.