@Dr1984 I'm sorry for your loss. Very similar to your case, I'm turning 38 soon and I had a miscarriage at around 6 weeks less month, and it was my first pregnancy. I'm still waiting for my first cycle to be back after the miscarriage. I have rather irregular cycles, range from 28 to 35 days. I tried to use ovulation tests two weeks after the miscarriage to see if I was ovulating (so as to predict my next cycle), but the results kept showing negative for a few days (while normally I should have been ovulating some day on that week).
But I just decided not to stress about it too much. I go on taking supplements and Chinese medicine to help my body getting back to normal, just go about my days as usual because it's normal that the cycle would delay after having miscarriage. I think right now what you can do is not being too negative and stressed about the whole situation. Eat healthy, take rest, do physical exercise... get your body and mind ready for the next pregnancy. Take supplements that can help you get pregnant easier, and like @moosey89 said, having acupuncture can help you regulate your cycle (and if you're open to it, you can try Chinese medicines too - I'm Asian and I think it works).
When I was in the hospital, all women in my ward were either having a miscarriage or having surgery due to eccyesis. We all lost our babies... but everyone of us were strong and we could talk to doctors and nurses very calmly (even though we quietly cried on our beds). Hearing their stories and knowing they had a rougher time (one of them had 2 eccyesis in a row, many of them needed surgery), I asked myself to toughen up, because it could have been worse... Of course I'm not saying that our feelings are not valid just because someone has it worse (I cried for a whole week after the miscarriage and I was a mess, and I still cry a little once in a while now...). We went through a huge loss, no matter how many weeks we were pregnant when we had the miscarriage. But what I'm feeling is, these women, including myself, who went through this loss and pain but still get back on our feet and try again, are all heroes. You're not alone.
You know what, I had this pregnancy from IVF, which was my first. Actually I had never wanted to have kids until I turned 37. My husband and I then had some body checks and found out we're basically infertile (his sperm quality wasn't good and my AMH was only 0.3), and so we decided not to waste time trying conceive naturally and had our first IVF in August. I only had 2 eggs extracted and only 1 of them was successfully fertilized, which meant I only had 1 embryo implanted and got pregnant, though I ended up lost it in week 6... But I saw it as a good start, I'm going to try again when my cycle is back to normal. Getting pregnant at our age isn't easy but it's not impossible. Don't give up just yet. If you're very worried, you may have a blood test to check your AMH level and see if you need any clinical help. But the fact that you could conceive naturally the first time, I think you're not that bad. Once again, lead a healthy lifestyle, don't worry too much and don't be too depressed (negative emotions are not very good for conceiving). The baby is on the way!