I feel this overwhelming sense that there is something around like eyes are on me and it almost makes me fall over. Could this be a spirit?

They are eyes of God watching your ways and the eyes of your guardian angel taking charge over you.Or maybe you build your subconsious mind to be fearfull over mere imaginations.

It could mean that there is a spirit near you, but just that alone would not be a sure sign of a spirit. Another common thing that will cause those type of feelings are high EMF (electromagnetic field) readings. High EMF can cause feeling of being watched, nausea, hallucinations, and other things that are also signs of the paranormal. Does this happen in a certain spot, or room, or is it a feeling that can occur anytime, or place? EMF can be caused by anything that uses electricity to run such as TV, radio, phone chargers, fridge, clocks, and so on.

it happends in random times

it happends in random times
Is there anything in common with the feeling? Near large appliances, power boxes? If not then it may be something paranormal, but you need to eliminate any other possibilities before jumping to that conclusion. Has there been anything else that has happened aside from the feelings?

One time I got the feeling and I blacked out and woke up at the bottom of the stairs

one time i got the feeling and i blacked out and woke up at the bottom of the stairs

That is a bit of a concern, but may also be able to be explained by medical reasons. I am not trying to be rude, but have you gotten yourself checked out by a doctor about any of these feelings? I would hate to think that we were chasing spirits when there may be a medical problem. It is best to check out all causes before jumping to paranormal just off a feeling alone.

I will thanks for your help