Is there something wrong with my macbook?

So I just got my new MacBook Pro last month. I usually take serious caution with the security in mac. However, I noticed something weird this time. My mac used more than 12GB out of 16GB of RAM with 2 tabs on firefox open and imessages. I tried opening a lot of tabs in Chrome, Safari and Firefox and noticed that they take pretty long to load. I ran clamxav and saw 3 phishing emails so I removed them. In short, I am not sure if there's something wrong with my Mac but I set it up as a new computer and I usually learned from my past experience (this is my 3rd macbook) to keep my computer safe.

The different things I've done with this computer so far (applications installed wise) is using VPN with Tunnelblick and installing XBMC.

I also noticed whenever I reboot my computer, there will be something stopped working . I only rebooted it 3 times so far. The first time Photoshop broke. The second time Clamxav broke (it said it was tampered with ??). The 3rd time, Tunnelblick broke (also said it was tampered with and couldn't find the digital signature for the software).

Can someone please point me to doing something other than wipe my computer clean and reinstall everything?

Thank you

something is wrong; however, not enough to go on. You could try to look at the logs under console; consider turning off all network connections, then see what happens if you use the growers to open files.

You mention two open source softwares, You may want to startup with on app at a time and see when the problem occurs.

I suspect the easy fix is to reinstall from scratch; however, check what you put back on as well.

12/20/14 12:03:28.030 Spotlight[298]: CoreAnimation: warning, deleted thread with uncommitted CATransaction; set CA_DEBUG_TRANSACTIONS=1 in environment to log backtraces.

12/20/14 11:54:11.276 apsd[50]: Illegal subject name missing 'courier.push.apple.com' (2.5.4.3): ({

I definitely am not someone who can read logs so are these normal?

I think I will reinstall the OS