Yikes, I really "screwed up "

Well I have done it now...Not sure it was the right thing to do.. I am really confused about my internet connection and use of my modem. I have never had official computer lessons, as I have always pretty much practiced the trial & error method of anything.  Today I bought a new cell phone and a new modem to use for my internet connection since we have no good reception without an external dial up modem. I had gone over my allotted amount of 5g usage last month so I learned now I could have solved this problem another way & decided to "tether" my new phone capability to make sure that doesn't happen again..  Thats what the tech support person told me...and willl save me  money in the long run...Long story short.... Now I can use both a modem & my cell phone for connecting to the WWW. However.. Until the 20th of this month I am really "Screwed" If I use my phone for relief from adding more Overage on the modem... I cannot use my phone separately. I planned to be out of the state for a few weeks and Clay needs the computer so I cannot take it along.. but I  will want  & need my phone?  * are you following me here?," Do I suck it up , bite the  bullet and pay a HUGE bill by continue using the modem adding more overage fees, stop using the computer all together... That means no blogging, email or web surfing... YIKES" or do I forfeit my cell..phone? I cannot  do that. I was on the landline with the tech support for over 2 hours while he walked me through the whole downloading process.  Now we are on first name basis..but I probably wouldn't get him again if I called tech support...although he was very helpful, pleasant and made me feel not so stupid.....I told you I am not totally computer literate...Oh What to do? Maybe  I'll best use the cell phone connection  only for backup..? and go ahead   re hook up the modem? Clay knows even less than I do about this stuff... of course, so it will be impossible to explain to him  how to simply hook up or un hook the connection.......so bear with me....I will not be posting as much until I return March 1st.
I think I will pre post a few blog entries and let go of the connection. I can use my daughters computer when I get to Washington. That will be the smartest thing to do...and pay the price of overage use... grrrrrrrrrrrrrr I think I need a tall glass of wine right now...after I disconnect my phone.....so good bye for now... I"ll be back posting soon.