The many reasons why a guy would say he's thinking about you may not be obvious to you so let's clear up ANY confusion you might be having today.
FIRST.. and this will put your question about a man in complete perspective.
As a guy, I would NEVER, ever, ever call up another guy (or woman) friend, text him, or even dare mention to him,
"I was thinking about you and just decided to tell you."
With that said...
When he says he is thinking about you - it means he wants to see you again... among other things.
Something reminded him of you in a good or even sexual way.
He's thinking if he tells you, you'll see it as a lovely romantic gesture.
He's also trying to tell you that he's interested in you.
In what way remains to be seen because a guy will say it just as easily if he's looking for sex, that night, or somewhere down the road.
There's almost always an intimate or sexual attachment to the "I'm thinking about you." statement or message.
Now before you get too excited over the guy who sent this message or told you, it's not ALL love and romance.
Rarely - because I have done this myself - a guy will do it when he's looking for sex or for an intimate "sexting" romp. (If you can call it that.)
Other guys - the ones who are not all that good in the reading women part - are using it to fish for a response about how you feel about HIM.
So he might not mean it that much - sorry.
If you answer "Awww that's sweet." he'll probably see it as friendly response either confusing him more or leading him to believe you don't feel the same way as him.
NO guy who is feeling it for a woman AND decides to tell her he's thinking about her, wants to hear anything but...
"I miss you too!"
Of course you could come back with a clever flirty thing - he might assume you're interested as much as he is - but that's no guarantee because without a CLEAR signal from you, he still might not get it.
Everyone knows or assume guys are thinking about women all the time. Which is true for the younger one but as they age, it lessens.
A younger guy telling you he is thinking about you might mean something totally different than an older guy.
Here are some examples to help you decide the full extent to what he means.
When a guy wakes up thinking about you he's feeling more than just attraction.
If you tells you, "Just woke up and was thinking about you." It can certainly be a sign he wants you to wake up with him.
When a guy texts you that something he saw just reminded him of you and messages, "Just saw... and it made me think about you." - that's normally his way of connecting with you.
Some guys even do it to increase your attraction to him. It's a "technique" we teach guys.
Which means he's attracted to you. From this context it's hard to tell if he's looking for more.
When a guy you're dating is out of town or far away and he tells you he's thinking about - it's a good sign that he's trying to form a deeper connection with you.
Which means - all things aside - he's probably interested in something more than casual sex.
Guys at some point, must step back from the woman they're dating and think about what is happening.
If you're the one he's focused on - then he'll tell you he misses you. Which is a little deeper than "thinking about you" but it can mean the same thing to a guy.
He's also telling you, "I'm feeling something for you and I DO want to see you again."
I'd say that's the whole of this answer.
Men tend to be direct with their words even if it doesn't feel that way.
When he says he's thinking about you - it simply means HE IS doing just that... you're on his mind.
It's not always going to be possible to figure out the deeper meaning when it's out of context.
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