Feel like I'm dying...Constantly

[ITU-HCA]

Ok all so I have severe health anxiety which primarily focuses on me heart !

I've had a number (countless infact) ECGS which have been reported as normal cholesterol is borderline high, coronary calcium score from 2011 zero giving me (according to GP) significantly low risk of an MI!
However I can't believe this slightest pain in chest and I'm panicking so now too present...

Yesterday I was at A&E due to severe pain caused by a pilonidol cyst in my upper bum crack (coccyx) I had this lanced and drained by scalpel there and then and shortly after I asked an A&E dr why my pulse was so high (around 110/120) she put this down too anxiety and pain but performed an ECG too be safe...ecgvwas reported by her shortly after as normal but with fast pulse / sinus tachycardia !! Happily I went home and been in lots of pain since due to my cyst which couldn't be fully drained as in inflamed
Now today... pulse has generally been ok and until my car did a runner I was (for once) having a happy day however when I spent a good half hour looking for her I noticed my pulse (via Fitbit) go as high as 141 / 138 so did my usual went indoors and laid on my bed which made my pulse come back down to high 90s and 100 so all good his eventually after 10 mins or so went down to my normal mid 80s upper 70s so thought no more of it. Later on lass wanted to go shopping so took her out on premise that I'd be going minor injury department to get my bum dressing changed as it was smelling and I couldn't really get to it to change it ... on going in my pulse again shot up too 141/148 however nurse practitioner didn't seem fazed he checked my pulse and said rhythm feels ok and as I wasn't sweating or had no chest pain it was likely anxiety + pain he also mentioned the ECG from day before backs this up. Left minor injuries and proceeded to go shopping pulse was up but not as bad maybe 90s / 134 at highest when I got home though me and lass had a barny so went in walked halfway upstairs realised I'd left my phone in car so went back to retrieve it. On getting back to my bed I checked my pulse and was mortified that it was 152 however this too dropped to normal levels (84) within minutes but since and up too now my pulse has been fluctuating between 90s to mid / high 90s up too what it is now 103 and isn't coming down !! (Freaking me out)
I've got a hot head but not profusely sweating or clammy, I get mild little pains in my chest which are fleeting and only last seconds (around rib line towards abdomen) but GP diagnosed costochondritis I'm also not dizzy and my breathing is normal I've rung 111 and they were happy I wasn't life threatening so have put me in a queue
I'm still freaking out though thinking it's my heart does anyone think it could be my heart due to my pulse issues or is it more likely my anxiety ?!
Please others give me examples of how you've felt in similar situations and how high has your pulse gone & how long has it remained elevated ...
I can't live like this no more [😭]

[Buster70]

Hi ,I've had a lot of heart worries this year but had the tests and have to put it down to anxiety apart from high blood pressure I checked out ok , my daughter has been realy stressed out at work and just by chance she checked her pulse on my phone app , it was constantly above 100 even when resting and she drove home from work it would be 120 to 140 , doc wasn't concerned but did blood tests they came back ok he also signed her off work for ten days untill she starts a new job , her pulse has now come down to the 80s she's only young so it's still a bit high but it shows constant stress will put your pulse up , is there anything stressing you ? Apart from this bloody anxiety , I can spend a whole day worrying about worrying , hope this is of some help , take care .