I switched from women’s 5% Rogaine to men’s 5% Kirkland Minoxidil, now I have shedding, should I switch back?

its unlikely that the switch in product is making you shed, but I would start hair products and growth factors (see link), in office PRP/acell, and get a formal evaluation to see if you have telogen stress shedding which may require hormonal optimization.  
I suggest a formal consultation as there are a combination of treatments that can be done to improve har loss.  Oral finesteride has very little to no side effects in the majority of people; PRP/platelet-rich plasma + stem cells like A Cell help regrow hair and slow down the thinning process; rogaine and restorsea spray should be used daily; oral viviscal helps keep nutrients high in the follices as well.  Transplantation is a last resort but works early in the aging process as well.  A formal consultation and combination treatment is needed.  Best, Dr. Emer. 

It’s not stronger just different. I would need to know your entire story from the last 3 years to tell you. If the prior Rogaine was not doing anything and now you switch to Kirkland minoxidil then yes you might shed and that could be a good thing. In this case you would want to stay on the new product. But I don’t have enough information from you! If the Rogaine was working just fine and you felt things were doing okay and then you switched to Kirkland because that’s all you can find then you must get back to the old product as soon as possible. If you are shedding because 2-3 months ago you had new stress in your life or you developed a thyroid problem or low iron or had weight loss or had fever or had surgery or started some other pills ... then this whole discussion about minoxidil is irrelevant because it’s not the minoxidil that is the problem in this last scenario. I would encourage you to review things with your doctor.

In theory the two minoxidil should be the exact same material, but returning to the woman's 5% makes sense at this time to see what happens