Where the heck are you? At 20 you were in Juja. and really really disliking the country living. Are you still in Thika? Are you in the city? Do you have a house? Do you like where you live? Hey, did you ever do that major move - like to US, like you were dreaming about once? Remember? Or somewhere else foreign where you could really enjoy?
Did you become the best you?quit smoking?
Did you become the best programmer $ entreprenuer
If you're single still, are you happy? Can you cope with being single at 25? Did you just give up on finding someone that felt like the other half of your soul? If you did give up, are you sure that's the right choice?
Remember all that debt chasing you around? And the job uncertainty? And living in Juja? Please tell me you cleared all that up, but haven't over-indulged.
I know music is still all-important to you. You wouldn't be you if it weren't. Are you still listening to stuff that makes you feel something deep and worthwhile? Remember what you liked at 20? That G-eazy & witt Lowry self-important emotional stuff? Have you thrown all that away and found a new style again?

Remember your Ex? She was 18 back then. I'm sure she's gone now. You loved her so much. I'm sure this paragraph is killing you. It hurt just to write it. Remember how she loved to be chased and how she didn't follow any commands except "gimmie a kiss." I sincerely hope you found something to fill the huge void she has left in your heart. You'll know you've become a huge bastard if you think it's silly that this paragraph made your eyes swell up when you wrote it at 20.

Overall, I know you are still a happy guy at 25. Hopefully you've straightened out some things and are taking the changes like a champ, but basically I have confidence that you are the same person you were back then.
So from the 20 year-old me to the 25 year-old, keep up the good work. Maybe go back to http://futurme.org if it's around and write the 30 year-old you a note. *Haha Hope you have enough cash in your paypal account for that now*
Love,
Dennis