That's excellent that your supply is back up! Congratulations!!!
Here's some other items you might consider if you have this problem again and it turns out not to be related to your monthly cycle. Please note that I was in a different situation that you - unfortunately I was not able to stay home with my son, so I pumped 3-4 times a day after I went back to work, and he had free access evenings, nights, and weekends. Thank God I had a desk job! If I had worked on the shop floor all day, I don't think my employer would have been able to accommodate me. Each of my pumping sessions took an hour and a fifteen minutes, so I had to work through them at my laptop, and I had to pump at least 3 times a day or my supply would drop.
1) Type of breast pump can make a vast difference in the amount of milk you produce. For instance, I used a Medela Freestyle at work 3-4 times a day for 3-4 months starting when my son was 2.5 months old. It didn't work for me for various reasons (pain, suction level), but the biggest reason was one I didn't notice until some time had passed - my milk supply was decreasing. It wasn't fully emptying my breasts - eventually I was able to hand express 2 oz of milk after nothing else would come out using the pump. So I switched to the Medela Symphony, dealt with the rental costs, and was able to increase my supply and maintain it.
2) Exercise vs. food intake. In my case, I had to keep slowly gaining weight in order to produce enough milk over the entire year plus of pumping/nursing my son. I blame this on the fact that I was pumping some instead of BF exclusively, but for me it meant I couldn't exercise at all, or my supply would drop, and I couldn't decrease my caloric intake pretty much at all, or the same thing would happen. I love to exercise and really wanted to lose the baby weight. Drove me nuts.
3) Lip tie, tongue tie, or other physical issues with your baby's mouth. My son was born with a lip tie and a tongue tie, but was able to gain weight just fine. Most people fix such issues immediately, but I didn't want to put him through surgery as a newborn if it wasn't absolutely necessary. It was really hard to find someone who could tell me why nursing didn't feel quite right or was so difficult, but eventually we found a very experienced lactation consultant who caught what all the doctors and other lactation consultants had missed. With creative positioning on my part, nursing didn't feel too awful, so I dealt with his lip tie and tongue tie for five months. Around five months, he got bigger and his mouth changed size/shape, and all of a sudden nursing felt like torture. So I finally got his lip tie and tongue tie fixed, and all was well again with the nursing. Nursing time went from 45 minutes to 20 minutes, tops. I think because he had this issue, it didn't stimulate my breasts as much as he would have had his anatomy been normal, and this contributed to my problems with supply and the breast pump.
4) Diet. A friend of mine had to eat oatmeal every day to keep her supply up. This phenomena is actually pretty well known, and there's a variety of foods/supplements that can help.
5) Medications. It's pretty well known that nasal decongestants or other medications can decrease/dry up your milk supply. I took pseudoephedrine (Sudafed) for a cold, and I did see an effect on my milk supply, but it was relatively minor and my supply came back up pretty quickly. I hear other folks have not been so lucky.
6) Pregnancy. I would have liked to nurse my son longer than I did (I think we stopped around 16 months), but between him biting me to try out his new teeth and the soreness caused by my pregnancy with his sister, it was time for us to wean. I had no idea that my breasts would get as sore as they did. I had fully intended to nurse him through most of my pregnancy, but I just couldn't handle the pain.
Here's hoping you won't ever have to consider any of these possibilities and that your BF relationship is long and satisfying to you both!