I like this guy, what should I do?

Never jump to conclusions, this can lead to nothing good. However, be careful with this guy...from your question I find no reason to suspect anything good. Rule of thumb, when your dating a guy and it is early in the relationship, if you find suspect behavior you can document, be concerned, the future likely holds more of the same.

Don't accept a proposal if you don't feel like you're being treated the way you deserve to be treated. If you allow him to treat you poorly now, it definitely won't get any better as time goes on. You're still pretty young so I wouldn't rush it at all.

On another note are you always suspicious of him? He very well could have had a GUY friend over and they were passed out or being dumb playing video games. If this is the guy you want to marry you're going to have to trust him. Without trust (and communication) it will never work.

Listen to your heart and go with your gut feeling.