No, I only played dota 2 from the past month did no other steam related activities.
However I clicked some links shared under pc deals thread regarding some deals yesterday night (around 10) and when i reached home I was unable to login. When i checked my mail i had message at 10 pm yesterday that my email has been changed. Also I have steam security on, so when some one tries to login from new PC it sends a verification code, I didnt receive that too. The e-mail was changed bypassing it. BTW my e-mail is not hacked (though i changed the pwd anyway). Dont understand how they got through.
Also recently I used using Dotabuff, which asks for steam login credentials to login. However I have been using it since 2012 (though not regulary)
You said you clicked some links shared under PC deals thread. Is that on this forum? Can you be specific what links you clicked?
If any of the links leads to some suspicious sites, it needs to be removed right away.