Feelings of regret over career path?
dimas: Familiar feelings, ha ha.  I believe it is human nature to occasionally doubt what you and whether directions you are heading  is a right path.  I have heard it countless number of times.  Though at any given period of time you have to have predominant focus otherwise you will get lost in your choice and will never try either path.   The way I solve it, I just act upon the situation, circumstances and intuition coupled with my desires at particular moment of making a decision.   I wanted to get PHD in CS but ended up getting master because I was not sure what to concentrate in.   Well, now I am in the business world wondering what is next(I might still go for PHD but likely in different field than I though or have successful start up if not both) .   I have changed my directions several times but unless you try one you will never know if it is something for you or not.(and there is no negative outcome, you learn on the way plus get understanding if these is something you want or do not).  Just try what you believe is desirable and most optimal at this point, listen to your intuition and keep your eyes and mind open to opportunities when they are to come(you will know it).
Other thing I noticed, is depending what direction you chose your priorities change so your choose are likely to change along the line.   The only thing that works against you is time but that what our life is about.
Interesting that you mentioned philosophy, being technical with analytical mind, lately I started to get in more and more into philosophy; wonder if is a normal evolutionary trend for hackers or  it is just me…