How Long Does Your 8mo Brestfeed?

How long does your 8mo breastfeed in a session and total in a day? My son now feeds usually 5-12 mins and about 1.5 to 2 hours a day. We had an iron issue just before introducing solids. I believe it was mainly because my son has been too interested and distracted by the world since 4 months. Now I can pretty much only get him to breastfeed in a quiet and dark room. Almost never anywhere else. We had to bottle feed as well as breastfeed to make sure he got a large volume to get him back on track. Now I'm paranoid he'd not feeding enough just by breast, though he gulps when he's concentrating.