The best counsel I've ever heard on this topic is this:
Don't have another child if it will negatively affect the attention, care, time, and physical resources available to your existing children. (Your first two are here at your bidding, after all.) In your case, it sounds like your physical state during pregnancy may well make you less available to your two very young girls.
I've found that once I make a firm decision, the agonies over what I might miss out on gradually subside. If you give your best to your daughters, you may discover real satisfaction with what you already have. I chose to stop with one, because as much delight as I found in parenting, I also realized that I could REALLY do my best, emotionally and financially, for just one child. And it was a fabulous decision for my circumstances. I never regretted it after making it.
Enjoying pregnancy and/or babies is also an extremely one-sided view of whether or not to bring more kids into the world. I know this is not a convenient thing to hear, but at 62 years old, I am watching startling changes in our environment, and can see that the next generation or two may have staggering problems to deal with just to survive. I think it's acceptable to replace ourselves with one child each, but beyond that, we could deferring our own sense of loss or sacrifice onto future generations.