Hormones after childbirth

Hi mamas! I gave birth on April 16th to a lovely little girl. She hardly ever cries, has been sleeping through the night since week two... I have nothing to complain about when it comes to her. I also have a 6-year-old son and a sweetheart of a partner. My labor was painless and quick (I had an epidural), I didn't get any postpartum blues, and the time after was super happy. But around four months postpartum, everything suddenly became too much for me: obligations, housework, everything, even though I thought everything was going super well. I was just complaining because I couldn't handle it. Last month, 5 days after my period, I suddenly felt a bit anxious, but it was short-lived. This month, again 5 days after my period, I became anxious again, culminating in an anxiety/panic attack one evening. Last month my period came on the 24th day, and this month on the 36th day. I feel very insecure, currently slightly anxious with palpitations. I drink relaxation tea and valerian drops when needed. My thyroid is fine and I don't have a vitamin D deficiency either. After a half-hour walk, I feel exhausted, and even at home when I'm doing something for a little while. Then my body feels heavy, I get painful and watery eyes, and I feel completely drained, as if I've done heavy physical work all day. Does anyone relate to this? Is this part of the postpartum adjustment? It seems like a burnout and unbalanced hormones to me. Has anyone else experienced this around 6 months postpartum? By the way, I don't feel sad or depressed. Thanks in advance!