Am I doing enough around the house?

My husband commented this morning that I don't do enough around the house and I need to step it up. He was upset because his work clothes weren't washed. I work three 12 hr night shifts a week as a nurse, I'm 6 months pregnant, and we have an almost 15 month old. I do all the house hold chores, cooking, shopping, and taking care of a toddler when I'm not working. I also will get off work at 7:30 am and be up all day with my toddler. I live in a constant state of sleep deprivation. Yes, sometimes there are dishes in the sink, dirty laundry in the basket, Cheerios on the floor, but heck I'm doing the best I can. I don't have all my days off in a row so it's hard on me at times. I feel like his comment was a punch in the gut. I feel like he doesn't understand what I'm going through. I feel completely under appreciated. He does work a very physically demanding construction job 6 days a week and comes home and takes care of the yard and our huge veggie garden. He does work really hard and I appreciate it. But am I wrong? Do I need to pop some caffeine pills and try to do more to keep the house cleaner? I'm just really hurt after his comment.