Weakness/Fatigue 2 Months after IM Wisconsin

Hi all, I finished IM Wisconsin about 2 months ago, and ever since I have been experiencing some minor cognitive issues and muscle weakness/fatigue throughout my body that has made it difficult to get back into training. I've read that this is normal for this to occur for a few weeks following an IM, but I'm now at 2 months with no apparent improvement even though I've spent most of that time resting. I haven't been able to swim farther than 1000 yds or bike longer than a half hour because my body will stop allowing me to move. I'm also eating not that much less than I was during my training, so I'm not sure if it's a dietary issue. Just wondering if anyone here has had a similar experience and/or has any advice before I jump the gun and see a neurologist. Thanks in advance.