Thanks for your question. My name is XXXXX XXXXX I have over 10 years of experience helping people with relationship problems.
I can certainly understand why you would feel like things are moving very fast. It is possible that he firmly believes that he loves you, although it is somewhat of a mixed signal that he wasn't able to say it over the phone. It's understandable to be cautious about this man getting so emotionally involved so quickly, and while things may turn out perfectly fine, love is usually something that is easier to believe in once trust has been more firmly established, and that type of trust is hard to create in two months, even if everything seems perfect.
Unfortunately there isn't a perfect way to tell whether or not a man loves you, but I do think you'll know it when you get to that point. He may really mean that he loves you, but it also may not be possible for the relationship to have gotten to the point where you feel 100% confident in that love even if he believes it himself. If this is a man who falls in love quickly, you may want to consider taking the relationship at a reasonable pace until you are more confident that things will work out the way you hoped.
The other thing to consider is that he has been in a lot of pain, and is likely on medication for that pain. Both of those things can put someone into a heightened emotional state, so it is also possible that that is contributing to him being so emotional so quickly. He may still be very happy in your relationship, but also in somewhat of a complex emotional state himself which is reflected in the things he has been saying to you. It doesn't sound like there is any reason to doubt him, but at the same time after only two months it is understandable to be a little apprehensive about how quickly things are moving until you have established a deeper level of trust with him. At that point when he says that he loves you it will be much easier to tell and to believe it. I definitely wish you the best with all of this, and if there is anything else I can do to help please let me know.