!Help! Weird bug

[Skyler Mage]

I was playing HL2 this morning, riding the buggy. Then, a group of soldiers attacked me on the road, and the buggy was blocked by a stack of crashed cars in the middle of the road; so I got out of the buggy and took the (dunno the english name) Anti-Gravity gun to push the cars away, but the buggy and one car couldn't separate, so I went in the buggy to move it back.. But I couldn't get in it and I started to.. how to say that, vibrate? on top of the buggy, I couldn't do anything, I was stuck vibrating on top of the buggy, and when I finally managed to get out of it, I landed on the ground like if I fell from meters instead of the height of the buggy, I lose half of my life (this is not a pun about Half-Life).. I finally decided to go to the soldiers place walking, but I explored the road around the buggy before, and I found the crossbow (if it can help you to locate the place it happened). So I started running to the soldiers place, but halfway.. I was teleported next to the buggy again... I tried it again, fine this time. So I started to kill soldiers, but the weapons they drop when they die.. didn't drop; they were like.. levitating, and I couldn't take them.. I crashed some ammo crates, but couldn't take the ammo.. and a few meters away, I was magically teleported next to the buggy.. again -_-. So there might be a huge bug, did this (or something similar) happened to you? Thanks